Submission #12720

#	Time	Username	Problem	Language	Result	Execution time	Memory
12720		ainu7	The last wizard (kriii2_T)	C++98	4 / 4	644 ms	1676 KiB

T

#include <math.h>
#include <stdio.h>
#include <string.h>
#include <vector>
#include <string>
#include <queue>
#include <map>
#include <algorithm>
#include <cmath>
#include <iostream>
#include <sstream>
#include <set>
using namespace std;

const int mmod = 1000000007;

int pw(int a, long long b) {
  if (b == 0) return 1;
  int c = pw(a, b/2);
  c = (1LL * c * c) % mmod;
  if (b%2) c = (1LL * c * a) % mmod;
  return c;
}

int inv_mod(int a, int b) {
  if (a == 1) return b;
  int div = mmod / a + 1;
  return inv_mod((a * (long long)div) % mmod, (b * (long long)div) % mmod);
}

int combi(long long a, int b) {
  for (int i=0; i<b; i++)
    if ((a-i)%mmod == 0) return 0;
  int ret = 1;
  for (int i=0; i<b; i++) {
    ret = (1LL * ret * ((a-i)%mmod)) % mmod;
    ret = (1LL * ret * inv_mod(i+1, 1)) % mmod;
  }
  return ret;
}

int main()
{
  long long T;
  int N, A;
  cin >> T >> N >> A;
  int remain = A;
  int sum[1024] = {0};
  for (int i=0; i<N; i++) {
    int P;
    cin >> P;
    int Q[10];
    remain -= P;
    for (int j=0; j<10; j++)
      cin >> Q[j];
    for (int j=0; j<(1<<10); j++) {
      int now = P;
      for (int k=0; k<10; k++)
        if (j&(1<<k)) now = (1LL * now * Q[k]) % mmod;
      sum[j] = (sum[j] + now) % mmod;
    }
  }
  if (remain) {
    sum[0] = (sum[0] + remain) % mmod;
  }

  int res = pw(A, T);
  int prv[1<<10] = {0};
  prv[0] = 1;
  for (int i=1; i<=min(10LL, T); i++) {
    int nxt[1<<10] = {0};
    int com = combi(T, i);
    for (int j=0; j<(1<<10); j++) {
      nxt[j] = 0;
      for (int k=0; k<j; k++)
        if ((j&k) == k)
         nxt[j] = (nxt[j] + 1LL * prv[k] * sum[j-k]) % mmod;
    }
    for (int j=0; j<(1<<10); j++) {
      prv[j] = nxt[j];
      res = (res + ((1LL * prv[j] * com) % mmod) * pw(A, T-i)) % mmod;
    }
  }
  cout << res << endl;
}

• Subtask 1: 1 / 1
• Subtask 2: 3 / 3