View Compilation Error

0_0_29927054_2792.cpp: In function 'int main()':
0_0_29927054_2792.cpp:41:21: error: 'strcmp' was not declared in this scope
  while (strcmp(s,"0")) {
                     ^
0_0_29927054_2792.cpp:43:26: error: 'strlen' was not declared in this scope
   que[l].end = s[strlen(s) - 1];
                          ^
0_0_29927054_2792.cpp:63:30: error: 'memset' was not declared in this scope
    memset(vis, 0, sizeof(vis));
                              ^