dijkstra algorithm greedy c code example

Example 1: dijkstra algorithm c++

#include
using namespace std;

int main()
{
	int n = 9;
	
	int mat[9][9] = { { 100,4,100,100,100,100,100,8,100}, 
                      { 4,100,8,100,100,100,100,11,100}, 
                      {100,8,100,7,100,4,100,100,2}, 
                      {100,100,7,100,9,14,100,100,100}, 
                      {100,100,100,9,100,100,100,100,100}, 
                      {100,100,4,14,10,100,2,100,100}, 
                      {100,100,100,100,100,2,100,1,6}, 
                      {8,11,100,100,100,100,1,100,7}, 
                      {100,100,2,100,100,100,6,7,100}};
	
	int src = 0;
	int count = 1;
	
	int path[n];
	for(int i=0;i "<

Example 2: Dijkstra’s Algorithm code in C

#include#include#define INFINITY 9999#define MAX 10 void dijikstra(int G[MAX][MAX], int n, int startnode); void main(){	int G[MAX][MAX], i, j, n, u;	clrscr();	printf("\nEnter the no. of vertices:: ");	scanf("%d", &n);	printf("\nEnter the adjacency matrix::\n");	for(i=0;i < n;i++)		for(j=0;j < n;j++)			scanf("%d", &G[i][j]);	printf("\nEnter the starting node:: ");	scanf("%d", &u);	dijikstra(G,n,u);	getch();} void dijikstra(int G[MAX][MAX], int n, int startnode){	int cost[MAX][MAX], distance[MAX], pred[MAX];	int visited[MAX], count, mindistance, nextnode, i,j;	for(i=0;i < n;i++)		for(j=0;j < n;j++)			if(G[i][j]==0)				cost[i][j]=INFINITY;			else				cost[i][j]=G[i][j];		for(i=0;i< n;i++)	{		distance[i]=cost[startnode][i];		pred[i]=startnode;		visited[i]=0;	}	distance[startnode]=0;	visited[startnode]=1;	count=1;	while(count < n-1){		mindistance=INFINITY;		for(i=0;i < n;i++)			if(distance[i] < mindistance&&!visited[i])			{				mindistance=distance[i];				nextnode=i;			}		visited[nextnode]=1;		for(i=0;i < n;i++)			if(!visited[i])				if(mindistance+cost[nextnode][i] < distance[i])				{					distance[i]=mindistance+cost[nextnode][i];					pred[i]=nextnode;				}			count++;	} 	for(i=0;i < n;i++)		if(i!=startnode)		{			printf("\nDistance of %d = %d", i, distance[i]);			printf("\nPath = %d", i);			j=i;			do			{				j=pred[j];				printf(" <-%d", j);			}			while(j!=startnode);		}}

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