ZOJ Problem Set - 3708 Density of Power Network
http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=3708
#include <stdio.h> #include <string.h> int main(int argc, char *argv[]) { int T,i,j,lineSum; int N,M; int x[505],y[505]; int lineL [505][505] ; scanf("%d",&T); for(i = 0 ; i < T ;i++){ lineSum = 0; scanf("%d %d",&N,&M); memset (lineL,0,sizeof(lineL)); memset (lineL,0,sizeof(x)); memset (lineL,0,sizeof(y)); for(j = 0 ; j < M ;j++){ scanf("%d",&x[j]); } for(j = 0 ; j < M ;j++){ scanf("%d",&y[j]); } for(j = 0 ; j < M ;j++){ if(lineL[x[j]][y[j]] == 0 && lineL[y[j]][x[j]] == 0){ lineSum ++; lineL[x[j]][y[j]]=lineL[y[j]][x[j]]=1; } } printf("%.3f\n",lineSum/(N*1.0)); } return 0; }