Dada una array de costo costo[][] y una posición (m, n) en costo[][], escriba una función que devuelva el costo del camino de costo mínimo para alcanzar (m, n) desde (0, 0). Cada celda de la array representa un costo para atravesar esa celda. El costo total de un camino para llegar a (m, n) es la suma de todos los costos en ese camino (incluidos el origen y el destino). Solo puede atravesar celdas hacia abajo, hacia la derecha y en diagonal desde una celda determinada, es decir, desde una celda determinada (i, j), celdas (i+1, j), (i, j+1) y (i+1 , j+1) se puede atravesar. Puede suponer que todos los costos son números enteros positivos.
Por ejemplo, en la siguiente figura, ¿cuál es la ruta de costo mínimo a (2, 2)?
C++
// A Naive recursive implementation // of MCP(Minimum Cost Path) problem #include <bits/stdc++.h> using namespace std; #define R 3 #define C 3 int min(int x, int y, int z); // Returns cost of minimum cost path // from (0,0) to (m, n) in mat[R][C] int minCost(int cost[R][C], int m, int n) { if (n < 0 || m < 0) return INT_MAX; else if (m == 0 && n == 0) return cost[m][n]; else return cost[m][n] + min(minCost(cost, m - 1, n - 1), minCost(cost, m - 1, n), minCost(cost, m, n - 1)); } // A utility function that returns // minimum of 3 integers int min(int x, int y, int z) { if (x < y) return (x < z) ? x : z; else return (y < z) ? y : z; } // Driver code int main() { int cost[R][C] = { { 1, 2, 3 }, { 4, 8, 2 }, { 1, 5, 3 } }; cout << minCost(cost, 2, 2) << endl; return 0; } // This code is contributed by nikhilchhipa9
C
/* A Naive recursive implementation of MCP(Minimum Cost Path) problem */ #include<stdio.h> #include<limits.h> #define R 3 #define C 3 int min(int x, int y, int z); /* Returns cost of minimum cost path from (0,0) to (m, n) in mat[R][C]*/ int minCost(int cost[R][C], int m, int n) { if (n < 0 || m < 0) return INT_MAX; else if (m == 0 && n == 0) return cost[m][n]; else return cost[m][n] + min( minCost(cost, m-1, n-1), minCost(cost, m-1, n), minCost(cost, m, n-1) ); } /* A utility function that returns minimum of 3 integers */ int min(int x, int y, int z) { if (x < y) return (x < z)? x : z; else return (y < z)? y : z; } /* Driver program to test above functions */ int main() { int cost[R][C] = { {1, 2, 3}, {4, 8, 2}, {1, 5, 3} }; printf(" %d ", minCost(cost, 2, 2)); return 0; }
Java
/* A Naive recursive implementation of MCP(Minimum Cost Path) problem */ public class GFG { /* A utility function that returns minimum of 3 integers */ static int min(int x, int y, int z) { if (x < y) return (x < z) ? x : z; else return (y < z) ? y : z; } /* Returns cost of minimum cost path from (0,0) to (m, n) in mat[R][C]*/ static int minCost(int cost[][], int m, int n) { if (n < 0 || m < 0) return Integer.MAX_VALUE; else if (m == 0 && n == 0) return cost[m][n]; else return cost[m][n] + min( minCost(cost, m-1, n-1), minCost(cost, m-1, n), minCost(cost, m, n-1) ); } // Driver code public static void main(String args[]) { int cost[][] = { {1, 2, 3}, {4, 8, 2}, {1, 5, 3} }; System.out.print(minCost(cost, 2, 2)); } } // This code is contributed by Sam007
Python3
# A Naive recursive implementation of MCP(Minimum Cost Path) problem R = 3 C = 3 import sys # Returns cost of minimum cost path from (0,0) to (m, n) in mat[R][C] def minCost(cost, m, n): if (n < 0 or m < 0): return sys.maxsize elif (m == 0 and n == 0): return cost[m][n] else: return cost[m][n] + min( minCost(cost, m-1, n-1), minCost(cost, m-1, n), minCost(cost, m, n-1) ) #A utility function that returns minimum of 3 integers */ def min(x, y, z): if (x < y): return x if (x < z) else z else: return y if (y < z) else z # Driver program to test above functions cost= [ [1, 2, 3], [4, 8, 2], [1, 5, 3] ] print(minCost(cost, 2, 2)) # This code is contributed by # Smitha Dinesh Semwal
C#
/* A Naive recursive implementation of MCP(Minimum Cost Path) problem */ using System; class GFG { /* A utility function that returns minimum of 3 integers */ static int min(int x, int y, int z) { if (x < y) return ((x < z) ? x : z); else return ((y < z) ? y : z); } /* Returns cost of minimum cost path from (0,0) to (m, n) in mat[R][C]*/ static int minCost(int [,]cost, int m , int n) { if (n < 0 || m < 0) return int.MaxValue; else if (m == 0 && n == 0) return cost[m, n]; else return cost[m, n] + min(minCost(cost, m - 1, n - 1), minCost(cost, m - 1, n), minCost(cost, m, n - 1) ); } // Driver code public static void Main() { int [,]cost = {{1, 2, 3}, {4, 8, 2}, {1, 5, 3}}; Console.Write(minCost(cost, 2, 2)); } } // This code is contributed // by shiv_bhakt.
PHP
<?php /* A Naive recursive implementation of MCP(Minimum Cost Path) problem */ $R = 3; $C = 3; /* Returns cost of minimum cost path from (0,0) to (m, n) in mat[R][C]*/ function minCost($cost, $m, $n) { global $R; global $C; if ($n < 0 || $m < 0) return PHP_INT_MAX; else if ($m == 0 && $n == 0) return $cost[$m][$n]; else return $cost[$m][$n] + min1(minCost($cost, $m - 1, $n - 1), minCost($cost, $m - 1, $n), minCost($cost, $m, $n - 1) ); } /* A utility function that returns minimum of 3 integers */ function min1($x, $y, $z) { if ($x < $y) return ($x < $z)? $x : $z; else return ($y < $z)? $y : $z; } // Driver Code $cost = array(array(1, 2, 3), array (4, 8, 2), array (1, 5, 3)); echo minCost($cost, 2, 2); // This code is contributed by mits. ?>
Javascript
<script> // A Naive recursive implementation of // MCP(Minimum Cost Path) problem // A utility function that returns // minimum of 3 integers function min(x, y, z) { if (x < y) return (x < z) ? x : z; else return (y < z) ? y : z; } // Returns cost of minimum cost path // from (0,0) to (m, n) in mat[R][C] function minCost(cost, m, n) { if (n < 0 || m < 0) return Number.MAX_VALUE; else if (m == 0 && n == 0) return cost[m][n]; else return cost[m][n] + min(minCost(cost, m - 1, n - 1), minCost(cost, m - 1, n), minCost(cost, m, n - 1)); } // Driver code var cost = [ [ 1, 2, 3 ], [ 4, 8, 2 ], [ 1, 5, 3 ] ]; document.write(minCost(cost, 2, 2)); // This code is contributed by gauravrajput1 </script>
C++
/* Dynamic Programming implementation of MCP problem */ #include <bits/stdc++.h> #include<limits.h> #define R 3 #define C 3 using namespace std; int min(int x, int y, int z); int minCost(int cost[R][C], int m, int n) { int i, j; // Instead of following line, we can use int tc[m+1][n+1] or // dynamically allocate memory to save space. The following line is // used to keep the program simple and make it working on all compilers. int tc[R][C]; tc[0][0] = cost[0][0]; /* Initialize first column of total cost(tc) array */ for (i = 1; i <= m; i++) tc[i][0] = tc[i - 1][0] + cost[i][0]; /* Initialize first row of tc array */ for (j = 1; j <= n; j++) tc[0][j] = tc[0][j - 1] + cost[0][j]; /* Construct rest of the tc array */ for (i = 1; i <= m; i++) for (j = 1; j <= n; j++) tc[i][j] = min(tc[i - 1][j - 1], tc[i - 1][j], tc[i][j - 1]) + cost[i][j]; return tc[m][n]; } /* A utility function that returns minimum of 3 integers */ int min(int x, int y, int z) { if (x < y) return (x < z)? x : z; else return (y < z)? y : z; } /* Driver code*/ int main() { int cost[R][C] = { {1, 2, 3}, {4, 8, 2}, {1, 5, 3} }; cout << " " << minCost(cost, 2, 2); return 0; } // This code is contributed by shivanisinghss2110
C
/* Dynamic Programming implementation of MCP problem */ #include<stdio.h> #include<limits.h> #define R 3 #define C 3 int min(int x, int y, int z); int minCost(int cost[R][C], int m, int n) { int i, j; // Instead of following line, we can use int tc[m+1][n+1] or // dynamically allocate memory to save space. The following line is // used to keep the program simple and make it working on all compilers. int tc[R][C]; tc[0][0] = cost[0][0]; /* Initialize first column of total cost(tc) array */ for (i = 1; i <= m; i++) tc[i][0] = tc[i-1][0] + cost[i][0]; /* Initialize first row of tc array */ for (j = 1; j <= n; j++) tc[0][j] = tc[0][j-1] + cost[0][j]; /* Construct rest of the tc array */ for (i = 1; i <= m; i++) for (j = 1; j <= n; j++) tc[i][j] = min(tc[i-1][j-1], tc[i-1][j], tc[i][j-1]) + cost[i][j]; return tc[m][n]; } /* A utility function that returns minimum of 3 integers */ int min(int x, int y, int z) { if (x < y) return (x < z)? x : z; else return (y < z)? y : z; } /* Driver program to test above functions */ int main() { int cost[R][C] = { {1, 2, 3}, {4, 8, 2}, {1, 5, 3} }; printf(" %d ", minCost(cost, 2, 2)); return 0; }
Java
/* Java program for Dynamic Programming implementation of Min Cost Path problem */ import java.util.*; class MinimumCostPath { /* A utility function that returns minimum of 3 integers */ private static int min(int x, int y, int z) { if (x < y) return (x < z)? x : z; else return (y < z)? y : z; } private static int minCost(int cost[][], int m, int n) { int i, j; int tc[][]=new int[m+1][n+1]; tc[0][0] = cost[0][0]; /* Initialize first column of total cost(tc) array */ for (i = 1; i <= m; i++) tc[i][0] = tc[i-1][0] + cost[i][0]; /* Initialize first row of tc array */ for (j = 1; j <= n; j++) tc[0][j] = tc[0][j-1] + cost[0][j]; /* Construct rest of the tc array */ for (i = 1; i <= m; i++) for (j = 1; j <= n; j++) tc[i][j] = min(tc[i-1][j-1], tc[i-1][j], tc[i][j-1]) + cost[i][j]; return tc[m][n]; } /* Driver program to test above functions */ public static void main(String args[]) { int cost[][]= {{1, 2, 3}, {4, 8, 2}, {1, 5, 3}}; System.out.println(minCost(cost,2,2)); } } // This code is contributed by Pankaj Kumar
Python
# Dynamic Programming Python implementation of Min Cost Path # problem R = 3 C = 3 def minCost(cost, m, n): # Instead of following line, we can use int tc[m+1][n+1] or # dynamically allocate memoery to save space. The following # line is used to keep te program simple and make it working # on all compilers. tc = [[0 for x in range(C)] for x in range(R)] tc[0][0] = cost[0][0] # Initialize first column of total cost(tc) array for i in range(1, m+1): tc[i][0] = tc[i-1][0] + cost[i][0] # Initialize first row of tc array for j in range(1, n+1): tc[0][j] = tc[0][j-1] + cost[0][j] # Construct rest of the tc array for i in range(1, m+1): for j in range(1, n+1): tc[i][j] = min(tc[i-1][j-1], tc[i-1][j], tc[i][j-1]) + cost[i][j] return tc[m][n] # Driver program to test above functions cost = [[1, 2, 3], [4, 8, 2], [1, 5, 3]] print(minCost(cost, 2, 2)) # This code is contributed by Bhavya Jain
C#
// C# program for Dynamic Programming implementation // of Min Cost Path problem using System; class GFG { // A utility function that // returns minimum of 3 integers private static int min(int x, int y, int z) { if (x < y) return (x < z)? x : z; else return (y < z)? y : z; } private static int minCost(int [,]cost, int m, int n) { int i, j; int [,]tc=new int[m+1,n+1]; tc[0,0] = cost[0,0]; /* Initialize first column of total cost(tc) array */ for (i = 1; i <= m; i++) tc[i, 0] = tc[i - 1, 0] + cost[i, 0]; /* Initialize first row of tc array */ for (j = 1; j <= n; j++) tc[0, j] = tc[0, j - 1] + cost[0, j]; /* Construct rest of the tc array */ for (i = 1; i <= m; i++) for (j = 1; j <= n; j++) tc[i, j] = min(tc[i - 1, j - 1], tc[i - 1, j], tc[i, j - 1]) + cost[i, j]; return tc[m, n]; } // Driver program public static void Main() { int [,]cost= {{1, 2, 3}, {4, 8, 2}, {1, 5, 3}}; Console.Write(minCost(cost,2,2)); } } // This code is contributed by Sam007.
PHP
<?php // DP implementation // of MCP problem $R = 3; $C = 3; function minCost($cost, $m, $n) { global $R; global $C; // Instead of following line, // we can use int tc[m+1][n+1] // or dynamically allocate // memory to save space. The // following line is used to keep // the program simple and make // it working on all compilers. $tc; for ($i = 0; $i <= $R; $i++) for ($j = 0; $j <= $C; $j++) $tc[$i][$j] = 0; $tc[0][0] = $cost[0][0]; /* Initialize first column of total cost(tc) array */ for ($i = 1; $i <= $m; $i++) $tc[$i][0] = $tc[$i - 1][0] + $cost[$i][0]; /* Initialize first row of tc array */ for ($j = 1; $j <= $n; $j++) $tc[0][$j] = $tc[0][$j - 1] + $cost[0][$j]; /* Construct rest of the tc array */ for ($i = 1; $i <= $m; $i++) for ($j = 1; $j <= $n; $j++) // returns minimum of 3 integers $tc[$i][$j] = min($tc[$i - 1][$j - 1], $tc[$i - 1][$j], $tc[$i][$j - 1]) + $cost[$i][$j]; return $tc[$m][$n]; } // Driver Code $cost = array(array(1, 2, 3), array(4, 8, 2), array(1, 5, 3)); echo minCost($cost, 2, 2); // This code is contributed by mits ?>
Javascript
<script> // Javascript program for Dynamic Programming implementation // of Min Cost Path problem /* A utility function that returns minimum of 3 integers */ function min(x, y, z) { if (x < y) return (x < z)? x : z; else return (y < z)? y : z; } function minCost(cost, m, n) { let i, j; let tc = new Array(m+1); for(let k = 0; k < m + 1; k++) { tc[k] = new Array(n+1); } tc[0][0] = cost[0][0]; /* Initialize first column of total cost(tc) array */ for (i = 1; i <= m; i++) tc[i][0] = tc[i-1][0] + cost[i][0]; /* Initialize first row of tc array */ for (j = 1; j <= n; j++) tc[0][j] = tc[0][j-1] + cost[0][j]; /* Construct rest of the tc array */ for (i = 1; i <= m; i++) for (j = 1; j <= n; j++) tc[i][j] = Math.min(tc[i-1][j-1], tc[i-1][j], tc[i][j-1]) + cost[i][j]; return tc[m][n]; } let cost = [[1, 2, 3], [4, 8, 2], [1, 5, 3]]; document.write(minCost(cost,2,2)); </script>
C++
#include <bits/stdc++.h> using namespace std; #define row 3 #define col 3 int minCost(int cost[row][col]) { // for 1st column for (int i = 1; i < row; i++) cost[i][0] += cost[i - 1][0]; // for 1st row for (int j = 1; j < col; j++) cost[0][j] += cost[0][j - 1]; // for rest of the 2d matrix for (int i = 1; i < row; i++) for (int j = 1; j < col; j++) cost[i][j] += min(cost[i - 1][j - 1], min(cost[i - 1][j], cost[i][j - 1])); // returning the value in last cell return cost[row - 1][col - 1]; } int main(int argc, char const* argv[]) { int cost[row][col] = { { 1, 2, 3 }, { 4, 8, 2 }, { 1, 5, 3 } }; cout << minCost(cost) << endl; return 0; } // This code is contributed by Aditya Kumar (adityakumar129)
C
#include <stdio.h> #define row 3 #define col 3 // Find minimum between two numbers. int min(int num1, int num2) { return (num1 > num2) ? num2 : num1; } int minCost(int cost[row][col]) { // for 1st column for (int i = 1; i < row; i++) cost[i][0] += cost[i - 1][0]; // for 1st row for (int j = 1; j < col; j++) cost[0][j] += cost[0][j - 1]; // for rest of the 2d matrix for (int i = 1; i < row; i++) for (int j = 1; j < col; j++) cost[i][j] += min(cost[i - 1][j - 1], min(cost[i - 1][j], cost[i][j - 1])); // returning the value in last cell return cost[row - 1][col - 1]; } int main() { int cost[row][col] = { { 1, 2, 3 }, { 4, 8, 2 }, { 1, 5, 3 } }; printf("%d \n",minCost(cost)); return 0; } // This code is contributed by Aditya Kumar (adityakumar129)
Java
// Java program for the // above approach import java.util.*; class GFG{ static int row = 3; static int col = 3; static int minCost(int cost[][]) { // for 1st column for (int i = 1; i < row; i++) { cost[i][0] += cost[i - 1][0]; } // for 1st row for (int j = 1; j < col; j++) { cost[0][j] += cost[0][j - 1]; } // for rest of the 2d matrix for (int i = 1; i < row; i++) { for (int j = 1; j < col; j++) { cost[i][j] += Math.min(cost[i - 1][j - 1], Math.min(cost[i - 1][j], cost[i][j - 1])); } } // Returning the value in // last cell return cost[row - 1][col - 1]; } // Driver code public static void main(String[] args) { int cost[][] = {{1, 2, 3}, {4, 8, 2}, {1, 5, 3} }; System.out.print(minCost(cost) + "\n"); } } // This code is contributed by Amit Katiyar
Python3
# Python3 program for the # above approach def minCost(cost, row, col): # For 1st column for i in range(1, row): cost[i][0] += cost[i - 1][0] # For 1st row for j in range(1, col): cost[0][j] += cost[0][j - 1] # For rest of the 2d matrix for i in range(1, row): for j in range(1, col): cost[i][j] += (min(cost[i - 1][j - 1], min(cost[i - 1][j], cost[i][j - 1]))) # Returning the value in # last cell return cost[row - 1][col - 1] # Driver code if __name__ == '__main__': row = 3 col = 3 cost = [ [ 1, 2, 3 ], [ 4, 8, 2 ], [ 1, 5, 3 ] ] print(minCost(cost, row, col)); # This code is contributed by Amit Katiyar
C#
// C# program for the // above approach using System; class GFG{ static int row = 3; static int col = 3; static int minCost(int [,]cost) { // for 1st column for (int i = 1; i < row; i++) { cost[i, 0] += cost[i - 1, 0]; } // for 1st row for (int j = 1; j < col; j++) { cost[0, j] += cost[0, j - 1]; } // for rest of the 2d matrix for (int i = 1; i < row; i++) { for (int j = 1; j < col; j++) { cost[i,j] += Math.Min(cost[i - 1, j - 1], Math.Min(cost[i - 1, j], cost[i, j - 1])); } } // Returning the value in // last cell return cost[row - 1, col - 1]; } // Driver code public static void Main(String[] args) { int [,]cost = {{1, 2, 3}, {4, 8, 2}, {1, 5, 3} }; Console.Write(minCost(cost) + "\n"); } } // This code is contributed by Rajput-Ji
Javascript
<script> // javascript program for the // above approach var row = 3; var col = 3; function minCost(cost) { // for 1st column for (i = 1; i < row; i++) { cost[i][0] += cost[i - 1][0]; } // for 1st row for (j = 1; j < col; j++) { cost[0][j] += cost[0][j - 1]; } // for rest of the 2d matrix for (i = 1; i < row; i++) { for (j = 1; j < col; j++) { cost[i][j] += Math.min(cost[i - 1][j - 1], Math.min(cost[i - 1][j], cost[i][j - 1])); } } // Returning the value in // last cell return cost[row - 1][col - 1]; } // Driver code var cost = [[1, 2, 3], [4, 8, 2], [1, 5, 3] ]; document.write(minCost(cost) + '<br>'); // This code is contributed by 29AjayKumar </script>
C++
/* Minimum Cost Path using Dijkstra’s shortest path algorithm with Min Heap by dinglizeng */ #include <stdio.h> #include <queue> #include <limits.h> using namespace std; /* define the number of rows and the number of columns */ #define R 4 #define C 5 /* 8 possible moves */ int dx[] = {1,-1, 0, 0, 1, 1,-1,-1}; int dy[] = {0, 0, 1,-1, 1,-1, 1,-1}; /* The data structure to store the coordinates of \\ the unit square and the cost of path from the top left. */ struct Cell{ int x; int y; int cost; }; /* The compare class to be used by a Min Heap. * The greater than condition is used as this is for a Min Heap based on priority_queue. */ class mycomparison { public: bool operator() (const Cell &lhs, const Cell &rhs) const { return (lhs.cost > rhs.cost); } }; /* To verify whether a move is within the boundary. */ bool isSafe(int x, int y){ return x >= 0 && x < R && y >= 0 && y < C; } /* This solution is based on Dijkstra’s shortest path algorithm * For each unit square being visited, we examine all possible next moves in 8 directions, * calculate the accumulated cost of path for each next move, adjust the cost of path of the adjacent units to the minimum as needed. * then add the valid next moves into a Min Heap. * The Min Heap pops out the next move with the minimum accumulated cost of path. * Once the iteration reaches the last unit at the lower right corner, the minimum cost path will be returned. */ int minCost(int cost[R][C], int m, int n) { /* the array to store the accumulated cost of path from top left corner */ int dp[R][C]; /* the array to record whether a unit square has been visited */ bool visited[R][C]; /* Initialize these two arrays, set path cost to maximum integer value, each unit as not visited */ for(int i = 0; i < R; i++) { for(int j = 0; j < C; j++) { dp[i][j] = INT_MAX; visited[i][j] = false; } } /* Define a reverse priority queue. * Priority queue is a heap based implementation. * The default behavior of a priority queue is to have the maximum element at the top. * The compare class is used in the definition of the Min Heap. */ priority_queue<Cell, vector<Cell>, mycomparison> pq; /* initialize the starting top left unit with the cost and add it to the queue as the first move. */ dp[0][0] = cost[0][0]; pq.push({0, 0, cost[0][0]}); while(!pq.empty()) { /* pop a move from the queue, ignore the units already visited */ Cell cell = pq.top(); pq.pop(); int x = cell.x; int y = cell.y; if(visited[x][y]) continue; /* mark the current unit as visited */ visited[x][y] = true; /* examine all non-visited adjacent units in 8 directions * calculate the accumulated cost of path for each next move from this unit, * adjust the cost of path for each next adjacent units to the minimum if possible. */ for(int i = 0; i < 8; i++) { int next_x = x + dx[i]; int next_y = y + dy[i]; if(isSafe(next_x, next_y) && !visited[next_x][next_y]) { dp[next_x][next_y] = min(dp[next_x][next_y], dp[x][y] + cost[next_x][next_y]); pq.push({next_x, next_y, dp[next_x][next_y]}); } } } /* return the minimum cost path at the lower right corner */ return dp[m][n]; } /* Driver program to test above functions */ int main() { int cost[R][C] = { {1, 8, 8, 1, 5}, {4, 1, 1, 8, 1}, {4, 2, 8, 8, 1}, {1, 5, 8, 8, 1} }; printf(" %d ", minCost(cost, 3, 4)); return 0; }
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Artículo escrito por GeeksforGeeks-1 y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA