View Compilation Error

0_0_34561520_15499.cpp:12:10: error: array bound is not an integer constant before ']' token
 ll C[MAXN];
          ^
0_0_34561520_15499.cpp:17:9: error: array bound is not an integer constant before ']' token
 } A[MAXN], B[MAXN];
         ^
0_0_34561520_15499.cpp:17:18: error: array bound is not an integer constant before ']' token
 } A[MAXN], B[MAXN];
                  ^
0_0_34561520_15499.cpp: In function 'int main()':
0_0_34561520_15499.cpp:34:32: error: 'A' was not declared in this scope
             scanf("%lld%lld", &A[i].l, &A[i].r);
                                ^
0_0_34561520_15499.cpp:36:14: error: 'A' was not declared in this scope
         sort(A, A + n, cmp);
              ^
0_0_34561520_15499.cpp:39:9: error: 'B' was not declared in this scope
         B[c++] = A[0];
         ^
0_0_34561520_15499.cpp:52:9: error: 'C' was not declared in this scope
         C[0] = 0;
         ^