View Compilation Error

0_0_20478732_10006.cpp: In function 'int main()':
0_0_20478732_10006.cpp:13:3: error: 'a' was not declared in this scope
   a[i]=0;
   ^
0_0_20478732_10006.cpp:15:3: error: 'a' was not declared in this scope
   a[i]=1;
   ^
0_0_20478732_10006.cpp:17:3: error: 'a' was not declared in this scope
   a[i]=a[i-1]+a[i-2];
   ^
0_0_20478732_10006.cpp:19:29: error: 'a' was not declared in this scope
   printf("Case #%d: %d",k++,a[n]);
                             ^