SPFA

#include<stdio.h>#include<string.h>#include<stdlib.h>const int maxn=100,INF=1000000000;int a[maxn][maxn],p[maxn],d[maxn],q[maxn*maxn];int main(){freopen("spfa.in","r",stdin);freopen("spfa.out","w",stdout);int i,j,k,m,n;int x,y,z;scanf("%d%d",&n,&m);for(i=1;i<=m;i++){scanf("%d%d%d",&x,&y,&z);a[x][y]=z;}for(i=1;i<=n;i++)d[i]=INF;d[1]=0;q[1]=1;p[1]=1;int f=0,l=1;while(f<l){f++;k=q[f];for(i=1;i<=n;i++)if(a[k][i] && d[i]>d[k]+a[k][i]){d[i]=d[k]+a[k][i];if(!p[i]){q[++l]=i;p[i]=1;}}p[k]=0;}for(i=1;i<=n;i++)printf("%d ",d[i]);return 0;}

求某个点到所有点的最短路 与广搜思路类似 如果目标点不在队列内就添加入队