Dada una array arr[] , la tarea es encontrar el número más grande que se puede formar a partir de un par en la array dada.
Ejemplos:
Entrada: arr[] = { 3, 1, 9, 2 }
Salida: 93
El par (3, 9) conduce a la formación del número máximo 93
Entrada: arr[] = { 23, 14, 16, 25, 3, 9 }
Salida: 2523
El par (23, 25) conduce a la formación del número máximo 2523
Enfoque: La idea es formar todos los pares posibles de la array . Luego, para cada par X e Y , únalos como XY e YX y saque el máximo de todos esos pares.
para cada posible en la array (X, Y)
A continuación se muestra la implementación del enfoque anterior:
C++
// C++ implementation to find the
// greatest number from the
// given pairs of the array
#include <bits/stdc++.h>
using namespace std;
// Function to find the greatest
// number formed from the pairs
string getNumber(int a, int b)
{
string X = to_string(a);
string Y = to_string(b);
// first append Y at
// the end of X
string XY = X + Y;
// then append X at
// the end of Y
string YX = Y + X;
// Now see which of the
// two formed numbers
// is greater than other
return XY > YX ? XY : YX;
}
// Function to find pairs from array
void printMaxPair(int arr[], int n)
{
int largest = INT_MIN;
// Iterate through all pairs
for (int i = 0; i < n; i++)
for (int j = i + 1; j < n; j++) {
int number = stoi(
getNumber(arr[i], arr[j]));
largest = max(largest, number);
}
cout << largest;
}
// Driver code
int main()
{
int a[] = { 23, 14, 16, 25, 3, 9 };
int n = sizeof(a) / sizeof(a[0]);
printMaxPair(a, n);
return 0;
}
Java
// Java implementation to find the
// greatest number from the
// given pairs of the array
import java.util.*;
class GFG{
// Function to find the greatest
// number formed from the pairs
static String getNumber(int a, int b)
{
String X = Integer.toString(a);
String Y = Integer.toString(b);
// First append Y at
// the end of X
String XY = X + Y;
// Then append X at
// the end of Y
String YX = Y + X;
// Now see which of the
// two formed numbers
// is greater than other
return XY.compareTo(YX) > 0 ? XY : YX;
}
// Function to find pairs from array
static void printMaxPair(int arr[], int n)
{
int largest = Integer.MIN_VALUE;
// Iterate through all pairs
for(int i = 0; i < n; i++)
for(int j = i + 1; j < n; j++)
{
int number = Integer.parseInt(getNumber(arr[i],
arr[j]));
largest = Math.max(largest, number);
}
System.out.println(largest);
}
// Driver code
public static void main(String[] args)
{
int a[] = { 23, 14, 16, 25, 3, 9 };
int n = a.length;
printMaxPair(a, n);
}
}
// This code is contributed by offbeat
Python3
# Python3 implementation to find the # greatest number from the # given pairs of the array import sys; # Function to find the greatest # number formed from the pairs def getNumber(a, b): X = str(a); Y = str(b); # first append Y at # the end of X XY = X + Y; # then append X at # the end of Y YX = Y + X; # Now see which of the # two formed numbers # is greater than other if(XY > YX): return XY; else: return YX; # Function to find pairs from array def printMaxPair(arr, n): largest = -sys.maxsize - 1; # Iterate through all pairs for i in range(0, n): for j in range(i + 1, n): number = int(getNumber(arr[i], arr[j])); largest = max(largest, number); print(largest); # Driver code a = [ 23, 14, 16, 25, 3, 9 ]; n = len(a); printMaxPair(a, n); # This code is contributed by Code_Mech
C#
// C# implementation to find the
// greatest number from the
// given pairs of the array
using System;
class GFG{
// Function to find the greatest
// number formed from the pairs
static String getNumber(int a, int b)
{
String X = a.ToString();
String Y = b.ToString();
// First append Y at
// the end of X
String XY = X + Y;
// Then append X at
// the end of Y
String YX = Y + X;
// Now see which of the
// two formed numbers
// is greater than other
return XY.CompareTo(YX) > 0 ? XY : YX;
}
// Function to find pairs from array
static void printMaxPair(int []arr, int n)
{
int largest = int.MinValue;
// Iterate through all pairs
for(int i = 0; i < n; i++)
for(int j = i + 1; j < n; j++)
{
int number = Int32.Parse(getNumber(arr[i],
arr[j]));
largest = Math.Max(largest, number);
}
Console.WriteLine(largest);
}
// Driver code
public static void Main(String[] args)
{
int []a = { 23, 14, 16, 25, 3, 9 };
int n = a.Length;
printMaxPair(a, n);
}
}
// This code is contributed by Amit Katiyar
Javascript
<script>
// Javascript implementation to find the
// greatest number from the
// given pairs of the array
// Function to find the greatest
// number formed from the pairs
function getNumber(a, b)
{
var X = a.toString();
var Y = b.toString();
// first append Y at
// the end of X
var XY = X + Y;
// then append X at
// the end of Y
var YX = Y + X;
// Now see which of the
// two formed numbers
// is greater than other
return XY > YX ? XY : YX;
}
// Function to find pairs from array
function printMaxPair(arr, n)
{
var largest = -100000000;
// Iterate through all pairs
for (var i = 0; i < n; i++)
for (var j = i + 1; j < n; j++) {
var number = parseInt(
getNumber(arr[i], arr[j]));
largest = Math.max(largest, number);
}
document.write( largest);
}
// Driver code
var a = [ 23, 14, 16, 25, 3, 9];
var n = a.length;
printMaxPair(a, n);
</script>
Producción:
2523
Complejidad temporal: O(n 2 )
Espacio Auxiliar: O(1)