import sys def input(): return sys.stdin.readline().strip() MOD = 10**9 + 7 MAXI = 31 fac = [1] * (MAXI + 1) ifac = [1] * (MAXI + 1) for i in range(1, MAXI + 1): fac[i] = fac[i - 1] * i % MOD ifac[MAXI] = pow(fac[MAXI], MOD - 2, MOD) for i in range(MAXI, 0, -1): ifac[i - 1] = ifac[i] * i % MOD def c...