View Compilation Error

0_0_34941537_18796.cpp: In function 'int main()':
0_0_34941537_18796.cpp:11:28: error: 'strlen' was not declared in this scope
   for(int ix=0;ix!=strlen(s);ix++){
                            ^
0_0_34941537_18796.cpp:23:6: error: 'ix' was not declared in this scope
   if(ix==strlen(s))
      ^
0_0_34941537_18796.cpp:23:18: error: 'strlen' was not declared in this scope
   if(ix==strlen(s))
                  ^