/in/foo.c:2:6: warning: return type of 'main' is not 'int' [-Wmain]
 void main(){
      ^~~~
/in/foo.c: In function 'main':
/in/foo.c:4:16: error: invalid operands to binary & (have 'int *' and 'int')
 scanf("%d%d",&a&b);
              ~~^