POJ_1018_Communication System

////枚举+贪心，枚举每一个带宽作为最小带宽，然后寻找每一个设备中带宽大于或等于最小带宽但是价格最低////的设备，比较每一次B/P的结果，取最大值 #include<stdio.h>#include<time.h>int bp[105][205];int price,bandwidth;double max;int sort(int *num){int i,j;for(i=4;i<=2*num[0];i+=2){for(j=2*num[0];j>=i;j-=2){if(num[j]>num[j-2]){int t=num[j-1];num[j-1]=num[j-3];num[j-3]=t;t=num[j];num[j]=num[j-2];num[j-2]=t;}}}return 0;}int main(){//freopen("in.txt","r",stdin);//freopen("out1.txt","w",stdout);int cas;scanf("%d",&cas);while(cas--){int n;scanf("%d",&n);max=0.0;int i,j,k,t;for(i=0;i<n;i++){scanf("%d",&bp[i][0]);for(j=1;j<=2*bp[i][0];j++)scanf("%d",&bp[i][j]);sort(bp[i]);}for(i=0;i<n;i++){for(j=1;j<=2*bp[i][0];j+=2){bandwidth=bp[i][j];price=bp[i][j+1];for(k=0;k<n;k++){int low=100000;if(k==i)continue;for(t=1;t<=2*bp[k][0];t+=2){if(bp[k][t]>=bandwidth&&bp[k][t+1]<low)low=bp[k][t+1];if(bp[k][t]<bandwidth)break;}if(low==100000){bandwidth=0;break;}price+=low;}if(bandwidth/(double)price>max)max=bandwidth/(double)price;}}printf("%.3f/n",max);//printf("%lf/n",(double)clock()/CLOCKS_PER_SEC);}return 0;}