View Compilation Error

0_0_15322089_2621.cpp:4:11: error: '::main' must return 'int'
 void main()
           ^
0_0_15322089_2621.cpp: In function 'int main()':
0_0_15322089_2621.cpp:13:29: error: 'memset' was not declared in this scope
   memset(arr, N, sizeof(arr));
                             ^