View Compilation Error

0_0_35518065_9318.cpp: In function 'int main()':
0_0_35518065_9318.cpp:11:18: error: 'i' was not declared in this scope
    scanf("%d",&a[i]);
                  ^
0_0_35518065_9318.cpp:12:21: error: expected ';' before ')' token
   for(register int _)
                     ^
0_0_35518065_9318.cpp:12:21: error: expected primary-expression before ')' token
0_0_35518065_9318.cpp:12:21: error: expected ';' before ')' token
0_0_35518065_9318.cpp:13:2: error: expected primary-expression before '}' token
  } 
  ^