#include int main() { int n = 0; u_int64_t save = 0; int cur_num = 0; int digit_num = 0; int result = 0; scanf("%d", &n); for (int count = 0; count < 3 * n - 1; count++) { scanf("%d", &cur_num); for (int i = 0; i < 32; i++) { if (cur_num >> i & 1) { digit_num = save >> (i * 2) & 3; digit_num = (digit_num + 1) % 3; save = save & (~(3 << (i * 2))) | (digit_num << (i * 2)); } } } for (int i = 0; i < 32; i++) { if (save >> (i * 2) & 3) { result |= 1 << i; } } printf("%d", result); return 0; }