View Compilation Error

0_0_34987996_18028.cpp:2:11: error: '::main' must return 'int'
 void main()
           ^
0_0_34987996_18028.cpp: In function 'int main()':
0_0_34987996_18028.cpp:19:13: error: 'abs' was not declared in this scope
     if(abs(c)>abs(max))
             ^