View Compilation Error

0_0_13820996_3958.cpp: In function 'int main()':
0_0_13820996_3958.cpp:7:37: error: 'strcmp' was not declared in this scope
  while (cin >>psw &&strcmp(psw,"end"))
                                     ^
0_0_13820996_3958.cpp:10:27: error: 'strlen' was not declared in this scope
   for (i = 0; i<strlen(psw); i++)
                           ^