题解 | #合并表记录#

#include <iostream>
#include <sstream>
#include <unordered_map>
#include <map>
using namespace std;

int main() {
    map<int, int> res;
    int num;
    cin>>num;
    int index;
    int val;
    string s;
    for(int i = 0;i<num+1;i++){
        getline(cin,s);
        istringstream ss(s);
        ss>>index;
        ss>>val;
        if(s.size()==0){
            continue;
        }
        if(res.find(index)==res.end()){
            res.insert({index,val});
        }else{
            res[index] += val;
        }
    }
    for(auto x:res){
        cout<<x.first<<' '<<x.second<<endl;
    }
}
// 64 位输出请用 printf("%lld")