题目链接:Highways
没看题,看了输入输出。就有种似曾相识的感觉,果然和HDU1102 题相似度99%,可是也遇到一坑
cin输入居然TLE,cin的缓存不至于这么狠吧,题目非常水。矩阵已经告诉你了。就敲个模板就是了,5分钟。1A
题意就是打印,最小生成树的最大边权。改了改输入,水过
这个题完了。我的个人POJ计划进度以完毕 20/200,这当中主要是图论的题。等下周把POJ计划图论的题目打完,就回头打模拟!我就不信还能比图论难
#include <iostream> #include <cstdio> #include <cstring> #include <cstdlib> #include <algorithm> const int N = 501; const int INF = 1e8; using namespace std; int dis[N],mapp[N][N]; bool vis[N]; int n,ans; void init() { ans = 0; memset(vis,0,sizeof(vis)); } void Prim() { int pos,minn; for(int i = 0;i<n;i++) dis[i] = mapp[0][i]; vis[0] = true; for(int i = 0;i<n;i++) { minn = INF; for(int j = 0;j<n;j++) { if(!vis[j] && dis[j] < minn) { minn = dis[j]; pos = j; } } vis[pos] = true ; if(minn > ans && minn!=INF) ans = minn; for(int k = 0;k<n;k++) { if(!vis[k] && dis[k] > mapp[pos][k]) dis[k] = mapp[pos][k]; } } } int main() { int t; scanf("%d",&t); while(t--) { init(); scanf("%d",&n); for(int i = 0;i<n;i++) { for(int j = 0;j<n;j++) scanf("%d",&mapp[i][j]); } Prim(); printf("%d\n",ans); } return 0; }
HDU1102
#include <iostream> #include <stdio.h> #include <stdlib.h> #include <string.h> using namespace std; const int N = 110; const int MAX = 9999999; int map[N][N],n; int dis[N],vis[N]; int a,b; int sum = 0; int PRIM() { memset(dis,0,sizeof(dis)); for(int i=1;i<=n;i++) dis[i]=map[1][i]; vis[1]=1; int wz = 0; for(int i=2;i<=n;i++) { int min= MAX; for(int j=1;j<=n;j++) { if(dis[j]<min&&!vis[j]) { min=dis[j]; wz=j; } } if(min<MAX) { vis[wz]=1; sum+=min; } else return -1; for(int j=1;j<=n;j++) { if(!vis[j]&&map[wz][j]<dis[j]) dis[j]=map[wz][j]; } } return sum; } int main() { int q; while (~scanf("%d",&n)) { sum = 0; for(int i = 1;i<=n;i++) { for(int j = 1;j<=n;j++) { scanf("%d",&map[i][j]); } } memset(vis,0,sizeof(vis)); scanf("%d",&q); for(int i = 0;i<q;i++) { scanf("%d%d",&a,&b); map[a][b] = 0; map[b][a] = 0; } sum = PRIM(); printf("%d\n",sum); } return 0; }