/in/foo.cc: In function 'int main()':
/in/foo.cc:10:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s.length();i++)
              ~^~~~~~~~~~~
/in/foo.cc:13:16: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(s[i]>='A' && s[i]<='Z' || s[i]>='a' && s[i]<='z') s[i]+=x;
                 
/in/foo.cc:17:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if(!(s[i]>='A' && s[i]<='Z' || s[i]>='a' && s[i]<='z')) printf("%c",s[i]-26);else printf("%c",s[i]);