View Compilation Error

0_0_13855579_8682.cpp: In function 'int main()':
0_0_13855579_8682.cpp:39:33: error: 'strlen' was not declared in this scope
                 n = strlen(s + 1);
                                 ^
0_0_13855579_8682.cpp:40:46: error: 'memset' was not declared in this scope
                 memset(last, -1, sizeof(last));
                                              ^