dijkstra

This is a very important and easy algorithm,I write this in case that I will forget it again in the future~

Dijkstra

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#include<string.h>
#include<iostream>
using namespace std;
#define N 0x1f1f1f1f
int w[151][151];
int d[155];
int ans,vis[151];
int n,m;
void ()
{
int i,j,k,v,tmp;
memset(vis,0,sizeof(vis));
for(i=1;i<=n;i++)
d[i]=w[1][i];
d[1]=0;
vis[1]=1;
for(i=1;i<=n;i++)
{
tmp=N;
for(j=1;j<=n;j++)
{
if(tmp>d[j]&&!vis[j])
{
tmp=d[j];
v=j;
}
}
vis[v]=1;
for(k=1;k<=n;k++)
{
if(!vis[k])
d[k]=min(d[k],d[v]+w[v][k]);
}
}
}
int main()
{
while(~scanf("%d%d",&n,&m))
{
if(n==0&&m==0)break;
for(int i=1;i<=n;i++)
{
for(int j=1;j<=n;j++)
{
w[i][j]=0x1f1f1f1f;
}
}
for(int i=0;i<m;i++)
{
int a,b,dis;
scanf("%d%d%d",&a,&b,&dis);
if(w[a][b]>dis)
w[a][b]=w[b][a]=dis;
}
Dij();
printf("%dn",d[n]);
}
}