C++ Programming Code Examples
C++ > Computer Graphics Code Examples
Program to Implement Nearest Neighbour Algorithm
/* Program to Implement Nearest Neighbour Algorithm
This is a C++ Program to implement nearest neighbour algorithm to solve TSP. This C++ program implements the Travelling Salesman Problem which computes the minimum cost required to visit all the nodes by traversing across the edges only once. */
#include<stdio.h>
#include<conio.h>
#include<iostream>
using namespace std;
int c = 0, cost = 999;
int graph[4][4] = { { 0, 10, 15, 20 }, { 10, 0, 35, 25 }, { 15, 35, 0, 30 }, {
20, 25, 30, 0 } };
void swap(int *x, int *y)
{
int temp;
temp = *x;
*x = *y;
*y = temp;
}
void copy_array(int *a, int n)
{
int i, sum = 0;
for (i = 0; i <= n; i++)
{
sum += graph[a[i % 4]][a[(i + 1) % 4]];
}
if (cost > sum)
{
cost = sum;
}
}
void permute(int *a, int i, int n)
{
int j, k;
if (i == n)
{
copy_array(a, n);
}
else
{
for (j = i; j <= n; j++)
{
swap((a + i), (a + j));
permute(a, i + 1, n);
swap((a + i), (a + j));
}
}
}
int main()
{
int i, j;
int a[] = { 0, 1, 2, 3 };
permute(a, 0, 3);
cout << "minimum cost:" << cost << endl;
}
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