/in/foo.cc: In function 'int main()':
/in/foo.cc:8:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s.size();i++)
              ~^~~~~~~~~
/in/foo.cc:9:14: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  if(s[i]>='0'&&s[i]<='9'||s[i]>='A'&&s[i]<='Z'||s[i]>='a'&&s[i]<='z')
               
/in/foo.cc:9:58: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  if(s[i]>='0'&&s[i]<='9'||s[i]>='A'&&s[i]<='Z'||s[i]>='a'&&s[i]<='z')
                                                           
/in/foo.cc:9:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(s[i]>='0'&&s[i]<='9'||s[i]>='A'&&s[i]<='Z'||s[i]>='a'&&s[i]<='z')
  ^~
/in/foo.cc:11:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   cout<<ans;
   ^~~~