View Compilation Error

0_0_17267459_11304.cpp: In function 'void manachar(char*)':
0_0_17267459_11304.cpp:16:22: error: 'strlen' was not declared in this scope
     int l = strlen(ss);
                      ^
0_0_17267459_11304.cpp:18:31: error: 'memset' was not declared in this scope
     memset(len, 0, sizeof(len));
                               ^
0_0_17267459_11304.cpp: In function 'int main()':
0_0_17267459_11304.cpp:46:35: error: 'memset' was not declared in this scope
         memset(cnt, 0, sizeof(cnt));
                                   ^