Monistus

#include <bits/stdc++.h>
using namespace std;

queue<char> q;
 
int main() {
    string s;
    cin >> s;
    int n = s.size();
    for (int i = 0; i < n; ++i) {
        if (!isdigit(s[i]))
            q.push(s[i]);
        else {
            string mul = "";
            int d = s[i]-'0';
            for (int j = i+1; j <= i+d; ++j) {
                if (!isdigit(s[j]))
                    mul += s[j];
                else {
                    int d2 = s[j]-'0';
                    for (int k = j+1; k <= i+d && d2; ++k) {
                        mul += s[k];
                        --d2;
                    }
                    for (int k = 0; k < d2; ++k) 
                        mul += mul[k];
                }
            }
            for (char c : mul)
                q.push(c);
        }
    }
    while (q.size()) {
        cout << q.front();
        q.pop();
    }
}

Test 1

Group: 1, 2

Verdict: WRONG ANSWER

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: WRONG ANSWER

Test 4

Group: 1, 2

Verdict: WRONG ANSWER

Test 5

Group: 1, 2

Verdict: WRONG ANSWER

Test 6

Group: 1, 2

Verdict: WRONG ANSWER

Test 7

Group: 1, 2

Verdict: WRONG ANSWER

Test 8

Group: 2

Verdict: WRONG ANSWER

Test 9

Group: 2

Verdict: WRONG ANSWER

Test 10

Group: 2

Verdict: WRONG ANSWER

Test 11

Group: 2

Verdict: ACCEPTED

Test 12

Group: 2

Verdict: WRONG ANSWER

Test 13

Group: 2

Verdict: WRONG ANSWER

Test 14

Group: 2

Verdict: WRONG ANSWER