func_code_string: #include <bits/stdc++.h>   using namespace std;   long long bd(string n) {     string num = n;     long long dec_value = 0;     long long base = 1;     long long len = num.length();     for (long long i = len - 1; i >= 0; i--) {       if (num[i] ==  1 ) dec_value += base;       base = base * 2;     }     return dec_value;   }   long long db(long long n) {     for (long long i = 31; i >= 0; i--) {       long long k = n >> i;       if (k & 1)         cout <<  1 ;       else         cout <<  0 ;     }   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     long long l, r;     cin >> l >> r;     if (l < r) {       long long x = 64 - (__builtin_clzll(l ^ r));       long long y = 1;       long long ans = y << x;       ans--;       cout << ans;     } else       cout << 0;     return 0;   }   