PAT1037. Magic Coupon (25)

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int nc,np;
vector<int> vc,vp;
int tmp;
int i,j;
int total;
int main(){
	cin>>nc;
	for(i=0;i<nc;i++){
		cin>>tmp;
		vc.push_back(tmp);
	}
	cin>>np;
	for(int i=0;i<np;i++){
		cin>>tmp;
		vp.push_back(tmp);
	}
	sort(vc.begin(),vc.end());
	sort(vp.begin(),vp.end());
	int a=0,b=0;
	for(a=0;a<vc.size();a++){
		if(vc[a]>0) break;
	}
	for(b=0;b<vp.size();b++){
		if(vp[b]>0) break;
	}
	i=vc.size()-1;j=vp.size()-1;
	while((i>=a)&&(j>=b)){
		total+=vc[i]*vp[j];
		i--;
		j--;
	}
	int m=0,n=0;
	while(m<a&&n<b){
		total+=vc[m]*vp[n];
		m++;
		n++;
	}
	cout<<total<<endl;
    return 0;
}