View Compilation Error

0_0_38322957_10940.cpp: In function 'int main()':
0_0_38322957_10940.cpp:23:23: error: 'digits' was not declared in this scope
         printf("%d",a[digits-1]);
                       ^
0_0_38322957_10940.cpp:24:13: error: 'i' was not declared in this scope
         for(i=digits-2; i>=0; i--)
             ^