Merkkijono

#include <iostream>
#include <string>
 
 
std::string d(std::string s) {
  int l = s.length(); // length of the string // counter
                           // iterate over the string
  for (int i = 0; i < l; i++) {
    l = s.length();
    if (l <= 1) {
      return s;
    }
    int c = 1;
    // increment counter for every identical consecutive character, counter starts at 1 to include the character at i
    for (int j = 1; i + j < l; j++) {
      if (s.at(i) == s.at(i + j)) {
        c++;
      }
      else {
        break;
      }
    }
    if (c > 1) {
      s.erase(i, c); // erase c characters starting at index i
      i = -1; // i will be incremented to 0 when the loop starts again
    }
  }
  return s;
}
 
 
int main() {
  std::string s;
  std::cin >> s;
 
  std::cout << d(s);
 
  return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED