Bittijono

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

string s;
uint32_t a;
uint64_t t1[500001];
uint64_t t2[500001];

int main(){
  cin >> s;
  a=0;
  if(s[0] == '1'){
    t1[0] = 1;
    t2[0] = 0;
  }
  else{
    t2[0] = 1;
    t1[0] = 0;
  }
  for(uint32_t i=1; i<s.size(); i++){ 
    if(s[i] == '1'){
      t1[i] = t2[i-1]+1;
      t2[i] = t1[i-1];
    }
    else{
      t1[i] = t1[i-1];
      t2[i] = t2[i-1]+1;
    }
  }
  uint64_t ans = 0;
  for(uint32_t i=0; i<s.size(); i++){
    ans+= t2[i];
    //cout << t2[i] << "\n";
  }
  
  cout << ans << "\n";
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 1

Verdict: ACCEPTED

Test 7

Group: 1

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: ACCEPTED

Test 12

Group: 2

Verdict: ACCEPTED

Test 13

Group: 2

Verdict: ACCEPTED

Test 14

Group: 2

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED

Test 16

Group: 3

Verdict: ACCEPTED

Test 17

Group: 3

Verdict: ACCEPTED

Test 18

Group: 3

Verdict: ACCEPTED

Test 19

Group: 3

Verdict: ACCEPTED

Test 20

Group: 3

Verdict: ACCEPTED

Test 21

Group: 3

Verdict: ACCEPTED