View Compilation Error

0_0_18347560_25968.cpp: In function 'void input()':
0_0_18347560_25968.cpp:10:40: error: 'strcmp' was not declared in this scope
 while(scanf("%s%s",a,b)&&strcmp(a,"END")){vis[b]=a;}
                                        ^
0_0_18347560_25968.cpp: In function 'void Fun()':
0_0_18347560_25968.cpp:27:18: error: 'strcmp' was not declared in this scope
 if(strcmp(a,"END")==0) break;
                  ^