Submission #1058696

---

Source Code Expand

#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <deque>
#include <iomanip>
#include <iostream>
#include <limits>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <vector>
 
#define FOR(i,k,n) for (int (i)=(k); (i)<(n); ++(i))
#define rep(i,n) FOR(i,0,n)
#define pb push_back
#define all(v) begin(v), end(v)
#define debug(x) cerr<< #x <<": "<<x<<endl
#define debug2(x,y) cerr<< #x <<": "<< x <<", "<< #y <<": "<< y <<endl
 
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vector<int> > vvi;
typedef vector<ll> vll;
typedef vector<vector<ll> > vvll;
template<class T> using vv=vector<vector< T > >;
 
int mod = 1e9 + 7;
 
int main() {
  int n, k;
  cin >> n >> k;
  string s;
  cin >> s;
 
  //vv<vi> dp(n+1, vvi(601, vi(601, 0))); // i番目まで、suffixのminがjでmaxがlであるパターンの数
  vv<vi> dp(n+1); // i番目まで、suffixのminがjでmaxがlであるパターンの数
  rep (i, n+1) {
    dp[i].assign(i*2+1, vi(i*2+1, 0));
  }
  dp[0][0][0] = 1;
  //int mini, maxi, mini_, maxi_, j_, l_;
  int j_, l_;
  rep (i, n) {
    /*
    mini = max(0, (i-k+1)/2);
    maxi = min(i, (i+k)/2);
    mini_ = max(0, (i-k+2)/2);
    maxi_ = min(i+1, (i+1+k)/2);
    */

    switch (s[i]) {
    case '0':
      FOR (j, max(0, i-k), min(i*2, i+k) + 1) {
        FOR (l, j, min(i*2, i+k) + 1) {
          j_ = min(i+2, j+2);
          l_ = max(i+2, l+2);
          if (i+1-k <= j_ && l_ <= i+1+k) {
            dp[i+1][j_][l_] += dp[i][j][l];
            dp[i+1][j_][l_] %= mod;
          }
        }
      }
      break;
    case '1':
      FOR (j, max(0, i-k), min(i*2, i+k) + 1) {
        FOR (l, j, min(i*2, i+k) + 1) {
          j_ = min(i, j);
          l_ = max(i, l);
          if (i+1-k <= j_ && l_ <= i+1+k) {
            dp[i+1][j_][l_] += dp[i][j][l];
            dp[i+1][j_][l_] %= mod;
          }
        }
      }
      break;
    case '?':
      FOR (j, max(0, i-k), min(i*2, i+k) + 1) {
        FOR (l, j, min(i*2, i+k) + 1) {
          j_ = min(i+2, j+2);
          l_ = max(i+2, l+2);
          if (i+1-k <= j_ && l_ <= i+1+k) {
            dp[i+1][j_][l_] += dp[i][j][l];
            dp[i+1][j_][l_] %= mod;
          }

          j_ = min(i, j);
          l_ = max(i, l);
          if (i+1-k <= j_ && l_ <= i+1+k) {
            dp[i+1][j_][l_] += dp[i][j][l];
            dp[i+1][j_][l_] %= mod;
          }
        }
      }
      break;
    }
  }
  int ans = 0;
  FOR (j, max(0, n-k), min(n*2, n+k) + 1) {
    FOR (l, j, min(n*2, n+k) + 1) {
      ans += dp[n][j][l];
      ans %= mod;
    }
  }
  printf("%d\n", ans);
 
  return 0;
}

Submission Info

Judge Result