zoj 2326

来源：互联网发布：关于人工智能的弊端编辑：程序博客网时间：2024/05/29 11:15

最小生成树题目……

#include<stdio.h>#include<stdlib.h>#include<string.h>struct paths{char x[21];char y[21];float dis;}path[400];int cmp(const void *a,const void *b) //这里注意啦，qsort返回值是int型的，必然不能返回两数的差值！！！{return (*(struct paths*)a).dis>(*(struct paths*)b).dis?1:-1;}int find(int x,int *father){if(father[x]==x)return x;elsereturn find(father[x],father);}int main(){int m,n,j,father[400],i,A,B;char a[400][21];float len,count;scanf("%f",&len);scanf("%d",&n);for(i=0;i<n;i++)scanf("%s",a[i]);for(i=0;i<n;i++)father[i]=i;scanf("%d",&m);for(i=0;i<m;i++)scanf("%s%s%f",&path[i].x,&path[i].y,&path[i].dis);qsort(path,m,sizeof(path[0]),cmp);for(i=0,count=0;i<m;i++){for(j=0;j<n&&strcmp(a[j],path[i].x)!=0;j++){}A=find(j,father);for(j=0;j<n&&strcmp(a[j],path[i].y)!=0;j++){}B=find(j,father);if(A!=B){father[A]=B;count+=path[i].dis;}}if(count<=len)printf("Need %.1f miles of cable\n",count);elseprintf("Not enough cable\n");return 0;}