func_code_string: #include <bits/stdc++.h>   #pragma GCC optimize( O2 )   using namespace std;   const long long INF = 1e15 + 7;   const long long N = 2e5 + 10;   const long long mod = 998244353;   long long pow(long long x, long long y) {     long long res = 1;     while (y > (long long)0) {       if (y & (long long)1) res = ((res) * (x));       y = y >> (long long)1;       x = ((x) * (x));     }     return res;   }   long long powm(long long x, long long y, long long p) {     long long res = 1;     x = x % p;     while (y > (long long)0) {       if (y & (long long)1) res = (res * x) % p;       y >>= (long long)1;       x = (x * x) % p;     }     return res;   }   void solve() {     long long n;     cin >> n;     string s;     cin >> s;     long long w = 0, b = 0;     vector<long long> v;     for (long long i = 0; i < n; i++) {       if (s[i] ==  B )         b++;       else         w++;     }     if (b % 2 != 0 && w % 2 != 0) {       cout << -1 << endl;       return;     }     if (b % 2 == 0) {       for (long long i = 0; i < n - 1; i++) {         if (s[i] ==  B ) {           s[i] =  W ;           if (s[i + 1] ==  B )             s[i + 1] =  W ;           else             s[i + 1] =  B ;           v.push_back(i + 1);         }       }     } else if (w % 2 == 0) {       for (long long i = 0; i < n - 1; i++) {         if (s[i] ==  W ) {           s[i] =  B ;           if (s[i + 1] ==  B )             s[i + 1] =  W ;           else             s[i + 1] =  B ;           v.push_back(i + 1);         }       }     }     cout << v.size() << endl;     for (auto i : v) cout << i <<    ;     cout << endl;     return;   }   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     long long ts = 1;     while (ts--) {       solve();     }   }   