View Compilation Error

0_0_34109972_4509.cpp: In function 'int main()':
0_0_34109972_4509.cpp:5:6: error: redeclaration of 'int n'
  int n;
      ^
0_0_34109972_4509.cpp:4:312: note: 'int n' previously declared here
  int A = 1, B = 2, C = 3, D = 4, E = 5, F = 6, G = 7, H = 8, I = 9, J = 10, K = 11, L = 12, M = 13, N = 14, O = 15, P = 16, Q = 17, R = 18, S = 19, T = 20, U = 21, V = 22, W = 23, X = 24, Y = 25, Z = 26, a = -1, b = -2, c = -3, d = -4, e = -5, f = -6, g = -7, h = -8, i = 9, j = -10, k = -11, l = -12, m = -13, n = -14, o = -15, p = -16, q = -17, r = -18, s = -19, t = -20, u = -21, v = -22, w = -23, x = -24, y = -25, z = -26;
                                                                                                                                                                                                                                                                                                                        ^