View Compilation Error

0_0_38573671_26900.cpp: In function 'bool judge(int)':
0_0_38573671_26900.cpp:45:9: error: 'memset' was not declared in this scope
         memset(book, 0, sizeof(book));
         ^~~~~~
0_0_38573671_26900.cpp:45:9: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
0_0_38573671_26900.cpp:2:1:
+#include <cstring>
 #include<stdio.h>
0_0_38573671_26900.cpp:45:9:
         memset(book, 0, sizeof(book));
         ^~~~~~
0_0_38573671_26900.cpp: In function 'int main()':
0_0_38573671_26900.cpp:77:22: error: 'strlen' was not declared in this scope
             len[i] = strlen(ch[i]);
                      ^~~~~~
0_0_38573671_26900.cpp:77:22: note: 'strlen' is defined in header '<cstring>'; did you forget to '#include <cstring>'?