0_0_18620744_9312.cpp:30:11: error: '::main' must return 'int' void main() ^ 0_0_18620744_9312.cpp: In function 'int main()': 0_0_18620744_9312.cpp:35:29: error: 'memset' was not declared in this scope memset(map, 0, sizeof(map)); ^