View Compilation Error

0_0_26252364_23982.cpp: In function 'void output(int)':
0_0_26252364_23982.cpp:5:20: error: 'printf' was not declared in this scope
     printf("%d\n",x);
                    ^
0_0_26252364_23982.cpp: In function 'void BM(char*, int, char*, int)':
0_0_26252364_23982.cpp:52:55: error: 'max' was not declared in this scope
           j += max(bmGs[i], bmBc[y[i + j]] - m + 1 + i);///不匹配 跳到x的前缀和y匹配的地方
                                                       ^
0_0_26252364_23982.cpp: In function 'int main()':
0_0_26252364_23982.cpp:57:24: error: 'scanf' was not declared in this scope
     while(~scanf("%s",x)){
                        ^
0_0_26252364_23982.cpp:59:30: error: 'printf' was not declared in this scope
         printf("%s  %s\n",x,y);
                              ^
0_0_26252364_23982.cpp:60:22: error: 'strlen' was not declared in this scope
         BM(y,strlen(y),x,strlen(x));
                      ^