warhammer327

#include <bits/stdc++.h>
#define debug(x) printf("-----------------%d\n", x);
#define LEN sizeof(a) / sizeof(a[0])
#define MEM(arr, k) memset(arr, k, sizeof arr)
#define input freopen("01input.txt", "r", stdin)
#define output freopen("01output.txt", "w", stdout)
#define go                            \
    ios_base::sync_with_stdio(false); \
    cin.tie(0);                       \
    cout.tie(0);