Bittijono

#include <iostream>
#include <algorithm>
#include <string>
 
 
int main() {
    std::string line;
    std::getline(std::cin, line);
 
 
 
    auto left  = line.begin();
    auto right = line.begin();
 
    int s = std::count(line.begin(), line.end(), '0');
 
    while (right != line.end()) {
        if (left == right) {
            right++;
        }
 
        auto n = std::count(left, right, '1');
        if (n % 2 != 0 or n == 0) {
            right++;
        } else {
            while (left != line.begin()) {
                if (*(left - 1) != '1') {
                    left--;
                }
            }
 
            while (n % 2 == 0 and n != 0) {
                s++;
                left++;
                n = std::count(left, right, '1');
            }
        }
    }
 
    auto n = std::count(left, right, '1');
    while (n % 2 == 0 and n != 0) {
        s++;
        left++;
        n = std::count(left, right, '1');
    }
 
    std::cout << s << std::endl;
 
 
    return 0;
}

Test 1

Group: 1

Verdict: TIME LIMIT EXCEEDED

Test 2

Group: 1

Verdict: TIME LIMIT EXCEEDED

Test 3

Group: 1

Verdict: TIME LIMIT EXCEEDED

Test 4

Group: 1

Verdict: TIME LIMIT EXCEEDED

Test 5

Group: 1

Verdict: WRONG ANSWER

Test 6

Group: 1

Verdict: RUNTIME ERROR

Test 7

Group: 1

Verdict: RUNTIME ERROR

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 2

Verdict: WRONG ANSWER

Test 13

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 16

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 17

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 18

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 19

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 20

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 21

Group: 3

Verdict: RUNTIME ERROR