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.

Here is source code of the C++ Program to Implement Nearest Neighbour Algorithm. The C++ program is successfully compiled and run on a Linux system. The program output is also shown below.

`#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;

`}`

Output:

$ g++ TSPNearestNeighbour.cpp $ a.out minimum cost:80 ------------------ (program exited with code: 0) Press return to continue

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