View Compilation Error

0_0_17711179_20207.cpp:12:6: error: 'i' was not declared in this scope
 LL a[i];
      ^
0_0_17711179_20207.cpp: In function 'int main()':
0_0_17711179_20207.cpp:20:50: error: 'a' was not declared in this scope
     for (int i = 1; i <= N; i++) scanf("%I64d", &a[i]);
                                                  ^
0_0_17711179_20207.cpp:21:11: error: 'a' was not declared in this scope
     sort (a+1, a+N+1);
           ^
0_0_17711179_20207.cpp:23:7: error: 't' was not declared in this scope
       t = a[i];
       ^