poj 1018 dp

#include<cstdio>#include<cstring>#define INF 0x3f3f3f3f#define MAX(x,y) ((x)>(y)?(x):(y))#define MIN(x,y) ((x)>(y)?(y):(x))int dp[120][400];int main(){int T;scanf("%d",&T);while(T--){int n;scanf("%d",&n);memset(dp,0x3f,sizeof(dp));for(int i=1;i<=n;i++){int num;scanf("%d",&num);while(num--){int b,p;scanf("%d%d",&b,&p);if(i==1){dp[i][b]=MIN(dp[i][b],p);}else{for(int k=1;k<=400;k++){if(dp[i-1][k]!=INF){  if(b>=k)  dp[i][k]=MIN(dp[i][k],dp[i-1][k]+p);  else  dp[i][b]=MIN(dp[i][b],dp[i-1][k]+p);    }}}}}double res=0;for(int i=0;i<=400;i++){if(dp[n][i]!=INF){res=MAX(res,(double)i/dp[n][i]);}}printf("%.3lf\n",res);}}