View Compilation Error

0_0_28140766_1453.cpp: In function 'bool cmp(person, person)':
0_0_28140766_1453.cpp:12:30: error: 'strcmp' was not declared in this scope
   return strcmp(a.time,b.time)<0;
                              ^
0_0_28140766_1453.cpp:14:30: error: 'strcmp' was not declared in this scope
   return strcmp(a.name,b.name)<0;
                              ^
0_0_28140766_1453.cpp: In function 'int main()':
0_0_28140766_1453.cpp:31:35: error: 'strcmp' was not declared in this scope
    if(strcmp(a[i].time,a[i+1].time)==0)
                                   ^