Submission #817525

#	Time	Username	Problem	Language	Result	Execution time	Memory
817525		kwongweng	Snake Escaping (JOI18_snake_escaping)	C++17	0 / 100	2074 ms	9284 KiB

snake_escaping

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ll, int> li;
#define FOR(i, a, b) for(int i = a; i < b; i++)
#define ROF(i, a, b) for(int i = a; i >= b; i--)
#define ms memset
#define pb push_back
#define fi first
#define se second
 
int main(){
  ios::sync_with_stdio(false);
  freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
  int L, Q; cin>>L>>Q;
  string s; cin >> s;
  int dp[1<<L]; FOR(i,0,(1<<L)) dp[i]=s[i]-'0';
  int dp2[1<<L]; FOR(i,0,(1<<L)) dp2[i]=s[(1<<L)-1-i]-'0';
  FOR(i,0,L){
    FOR(mask,0,(1<<L)){
      if (mask & (1<<i)) {dp[mask] += dp[mask-(1<<i)]; dp2[mask] += dp2[mask-(1<<i)];}
    }
  }
  FOR(i,0,Q){
    string t; cin >> t; reverse(t.begin(), t.end());
    int cnt1=0, cnt2=0; FOR(j,0,L) {cnt1 += (t[j]=='?'); cnt2 += (t[j]=='1');}
    if (cnt1 <= 6){
      int ans = 0;
      vi a; int cur = 0;
      FOR(j,0,L){
        if (t[j]=='?') a.pb(j);
        else cur += (1<<j)*(t[j]-'0');
      }
      FOR(j,0,(1<<cnt1)){
        int val=0; FOR(k,0,cnt1){
          if (j & (1<<k)) val ^= (1<<a[k]);
        }
        //cout<<cur+val<<" ";
        ans+=s[cur+val]-'0';
      }
      cout<<ans<<'\n'; continue;
    }
    if (cnt2 <= 6){
      vi a; int cur=0;
      FOR(j,0,L){
        if (t[j]=='1') {a.pb(j); cur += (1<<j);}
        if (t[j]=='?') cur += (1<<j);
      }
      int ans = 0;
      FOR(j,0,(1<<cnt2)){
        int val=0; int num=0; FOR(k,0,cnt2){
          if (j & (1<<k)) {val ^= (1<<a[k]); num^=1;}
        }
        if (num) ans += dp[cur-val];
        else ans -= dp[cur-val];
      }
      cout<<ans<<'\n'; continue;
    }
    int cnt3=L-cnt1-cnt2; vi a; int cur=0;
    FOR(j,0,L){
      if (t[j] != '1') cur+= (1<<j);
      if (t[j] == '0') a.pb(j);
    }
    int ans=0;
    FOR(j,0,(1<<cnt3)){
      int val=0,num=0; FOR(k,0,cnt3){
        if (j & (1<<k)) {val ^= (1<<a[k]); num^=1;}
      }
      if (num) ans-=dp2[cur-val];
      else ans+=dp2[cur-val];
    }
    cout<<ans<<'\n';
  }
}

Compilation message (stderr)

snake_escaping.cpp: In function 'int main()':
snake_escaping.cpp:19:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |   freopen("input.txt", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
snake_escaping.cpp:20:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |   freopen("output.txt", "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 10
• Subtask 4: 0 / 53
• Subtask 5: 0 / 25