HDU1233

Prim算法：#include#include#include#include#include#include#includeusing namespace std;#define min(a,b) ((a)>(b)?(b):(a))#define inf 1000000int mat[101][101],n;void Prim(){int i,j,min_i,Min,sum=0;int dis[501];int flag[501];for( i=1 ; i <= n ; i++ )dis[i] = mat[i][1];memset( flag, 0, sizeof(flag));flag[1] = 1;for( i=2 ; i <= n ; i++ ){Min = inf;min_i=i;for( j=2 ; j <= n ; j++ )if(flag[j]==0 && dis[j]{Min = dis[j];min_i = j;}if(Min == inf) break;sum += Min;flag[min_i] = 1;for( j=2 ; j <= n ; j++ ){if(flag[j]==0 && dis[j]>mat[min_i][j])dis[j] = mat[min_i][j];}}printf("%d\n", sum);}int main(){while(scanf("%d",&n)&&n){int a,b,d; for(int i=0;i { scanf("%d%d%d",&a,&b,&d); mat[a][b]=mat[b][a]=d; } Prim();}return 0;}Kruskal算法：#include#include#include#include#include#include#includeusing namespace std;#define min(a,b) ((a)>(b)?(b):(a))#define N 101int fa[N],n;struct edge{int x,y,value;}e[10001];bool cmp(edge a,edge b){return a.value < b.value;}int find(int x){if(x==fa[x]) return x;return fa[x]=find(fa[x]);}void Kruskal(){int ans = 0;for(int i=1 ; i <= n ; ++i)fa[i] = i;sort(e,e+(n-1)*n/2,cmp);for(int i=0 ; i < n*(n-1)/2 ; ++i){int x = find(e[i].x);int y = find(e[i].y);if(x != y){ans += e[i].value;fa[x] = y;}}printf("%d\n",ans);}int main(){while(scanf("%d",&n)&&n){ for(int i=0;i scanf("%d%d%d",&e[i].x ,&e[i].y,&e[i].value ); //sort(e,e+(n-1)*n/2,cmp); Kruskal();}return 0;}