View Compilation Error

0_0_18012676_13950.cpp: In function 'int main()':
0_0_18012676_13950.cpp:74:42: error: 'strcmp' was not declared in this scope
  while (scanf("%s",str)&&strcmp(str,"END")!=0)
                                          ^
0_0_18012676_13950.cpp:76:19: error: 'strlen' was not declared in this scope
   len = strlen(str);
                   ^