题解 | #合并表记录#

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

int main() {
    unsigned n;
    cin >> n;
    map<unsigned, unsigned> table;
    while (n != 0) {
        unsigned index, value;
        cin >> index >> value;
        if (table.find(index) == table.cend())
            table[index] = value;
        else
            table[index] += value;
        --n;
    }
    for (const auto& u : table)
        cout << u.first << " " << u.second << endl;
    return 0;
}
// 64 位输出请用 printf("%lld")