foo.cpp: In function 'int Prlindrome(char*)':
foo.cpp:7:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(i = 0; i < strlen(arr)/2 ; i++)
             ~~^~~~~~~~~~~~~~~
foo.cpp: In function 'int ADD(char*, int)':
foo.cpp:16:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(i = 0;i < strlen(arr);i++)
            ~~^~~~~~~~~~~~~
foo.cpp:20:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i < strlen(arr))
        ~~^~~~~~~~~~~~~
foo.cpp:26:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i < strlen(arr1))
        ~~^~~~~~~~~~~~~~
foo.cpp: In function 'int main()':
foo.cpp:46:8: warning: unused variable 'i' [-Wunused-variable]
  int N,i=0,s=0;
        ^