View Compilation Error

0_0_27501713_31287.cpp:4:11: error: '::main' must return 'int'
 void main()
           ^
0_0_27501713_31287.cpp: In function 'int main()':
0_0_27501713_31287.cpp:9:29: error: 'memset' was not declared in this scope
         memset(a,0,sizeof(a));
                             ^