Monistus

input/code.cpp: In function 'std::string sievenna(std::string)':
input/code.cpp:16:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for(int i = 0; i < s.size(); i++){
      |                    ~~^~~~~~~~~~
input/code.cpp:21:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |         if(isdigit(c) && i < s.size()-x){
      |                          ~~^~~~~~~~~~~~

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

unordered_map<string, string> m;
bool k = false;

string sievenna(string s){

    int n = s.size();
    for(int i = 0; i < n; i++){
        if(isdigit(s[i]) && i >= n - (s[i] - '0')) return s;
    }

    string u = "";
    for(int i = 0; i < s.size(); i++){
 
        char c = s[i];
        int x = c - '0';
 
        if(isdigit(c) && i < s.size()-x){
            string b = s.substr(i + 1, x);
 
            if(m.find(b) != m.end()) b = m[b];
            else{
                m[b] = sievenna(b);
                b = m[b];
            }

            s.erase(i + 1, x);
            s.insert(i + 1, b+b);
            

        }
        else{
            u += c;
        }
    }
    return u;
}


int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    
    string s;
    cin >> s;

    cout << sievenna(s);
    
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: ACCEPTED

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 1, 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 2

Verdict: ACCEPTED

Test 14

Group: 2

Verdict: ACCEPTED