func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int a, b, c, i, j;     char e, f;     string s, x, y;     set<string> v;     cin >> x >> y;     x[0] = x[0] -  a  + 1 +  0 ;     a = x[0] -  a  + 1;     b = x[1] -  0  + 1;     e = x[0];     f = x[1];     y[0] = y[0] -  a  + 1 +  0 ;     v.insert(x);     v.insert(y);     for (i = 1; i <= 8; i++) {       s =   ;       s += x[0];       s += (i +  0 );       v.insert(s);       s =   ;       s += (i +  0 );       s += x[1];       v.insert(s);     }     s =   ;     s = x[0] + 1;     s += x[1] + 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] - 1;     s += x[1] + 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] + 2;     s += x[1] + 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] - 2;     s += x[1] + 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] + 1;     s += x[1] - 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] + 2;     s += x[1] - 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] - 1;     s += x[1] - 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = x[0] - 2;     s += x[1] - 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] + 1;     s += y[1] + 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] - 1;     s += y[1] + 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] + 2;     s += y[1] + 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] - 2;     s += y[1] + 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] + 1;     s += y[1] - 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] + 2;     s += y[1] - 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] - 1;     s += y[1] - 2;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     s =   ;     s = y[0] - 2;     s += y[1] - 1;     if (s[1] >=  1  && s[1] <=  8  && s[0] >=  1  && s[0] <=  8 ) {       v.insert(s);     }     cout << 64 - v.size() << endl;     return 0;   }   