HDU 1233 还是畅通问题

 

http://acm.hdu.edu.cn/showproblem.php?pid=1233

 

 

解题思路：用Prim算法求最小生成树，然后输出总权值。

 

#include <stdio.h>#include <string.h>#define size 100#define INIT 999999int Graph[size][size];long sum;void Prim(int N){int i,j;int min,locate;int dist[size];bool visited[size];memset(visited,0,sizeof(visited));for(i=1;i<=N;i++)dist[i] = Graph[1][i];visited[1] = true;for (j=2;j<=N;j++){min = INIT;for (i=1;i<=N;i++){if (!visited[i]&&dist[i]<min){min = dist[i];locate = i;}}sum+=min;visited[locate] = true;for (i=1;i<=N;i++){if (!visited[i]){if (dist[i]>Graph[locate][i]){dist[i] = Graph[locate][i];}}}}}int main(){int i,j,weight;int N,k;/*freopen("e://1.txt","r",stdin);*/while (scanf("%d",&N)!=EOF&&N){sum = 0;for(i=1;i<=N;i++){for(j=1;j<=N;j++)if(i==j)Graph[i][j] = 0;elseGraph[i][j] = INIT;}k = (N*(N-1))/2;while (k--){scanf("%d%d%d",&i,&j,&weight);Graph[i][j] = weight;Graph[j][i] = weight;}Prim(N);printf("%ld/n",sum);}return 0;}