Run id: 1080

Main.cc:3:1: error: 'string' does not name a type
 string s;
 ^
Main.cc: In function 'int a(int)':
Main.cc:17:15: error: 's' was not declared in this scope
     for(int i=s.size()-1;i>=0;i--){
               ^
Main.cc: In function 'int main()':
Main.cc:26:5: error: 'cin' was not declared in this scope
     cin>>n>>m;
     ^
Main.cc:27:10: error: 's' was not declared in this scope
     cin>>s;
          ^
Main.cc:37:9: error: 'cout' was not declared in this scope
         cout<b[j];
         ^
Main.cc: In function 'char zhuanhuan(int)':
Main.cc:13:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^