#include <iostream>
#include <map>
#include <string>
using namespace std;
 
int main() {
    int n; // jumlah senyawa
    cin >> n;
 
    map<string, int> unsurTotal; // menyimpan total atom setiap unsur
 
    for (int i = 0; i < n; i++) {
        string unsur;
        int jumlah;
        cin >> unsur >> jumlah;
        unsurTotal[unsur] += jumlah;
    }
 
    // menampilkan hasil
    for (auto it : unsurTotal) {
        cout << it.first << " " << it.second << " ";
    }
    cout << endl;
    return 0;
}
 

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MSBDIDEgSCAzIENsIDEKMiBIIDIgTyAx

1 C 1 H 3 Cl 1
2 H 2 O 1