View Compilation Error

0_0_36081783_29394.cpp:5:11: error: '::main' must return 'int'
 void main() {
           ^
0_0_36081783_29394.cpp: In function 'int main()':
0_0_36081783_29394.cpp:36:35: error: 'memset' was not declared in this scope
         memset(str, a, sizeof(str));
                                   ^