View Compilation Error

0_0_25066108_835.cpp:3:11: error: '::main' must return 'int'
 void main()
           ^
0_0_25066108_835.cpp: In function 'int main()':
0_0_25066108_835.cpp:21:15: error: 'i' was not declared in this scope
          if(a[i-1]=='5')
               ^
0_0_25066108_835.cpp:23:14: error: 'i' was not declared in this scope
          for(i=1;i<j+1;i++)
              ^