c005. 環保獎金、UVA 10300 - Ecological Premium

 #include<stdio.h>
 #include<stdlib.h>
 
 int main(){
        int c, i, j, n  ;
        long long int farm[3] ;
        long long int sum ; 
        while(scanf("%d",&c)==1){
                for(i=0 ; i<c ; ++i){
                        sum = 0 ;
                        scanf("%d",&n) ;
                        for(j=0 ; j<n ; ++j){
                                scanf("%lld %lld %lld",&farm[0],&farm[1],&farm[2]) ; 
                                sum += farm[0]*farm[2] ;
                        }
                        printf("%lld\n",sum) ; 
                }
        }
        return 0 ;
 }