Submission #895195

#	Time	Username	Problem	Language	Result	Execution time	Memory
895195		alexander707070	Misspelling (JOI22_misspelling)	C++14	0 / 100	1 ms	6492 KiB

misspelling

#include<bits/stdc++.h>
#define MAXN 500007
using namespace std;

const int mod=1e9+7;

int n,m,a,b,ans;

int dp[MAXN][2][2][30];
bool li[MAXN][2][2][30];

int cnt[MAXN],pref[MAXN],cnt2[MAXN],pref2[MAXN];

int ff(int pos,int small,int big,int last){
    if(small==0 and cnt[pos]>0)small=1;
    if(small==1 and pref[pos]==0)small=0;

    if(big==0 and cnt2[pos]>0)big=1;
    if(big==1 and pref2[pos]==0)big=0;

    if(pos==n+1)return 1;

    if(li[pos][small][big][last])return dp[pos][small][big][last];
    li[pos][small][big][last]=true;

    for(int i=0;i<26;i++){
        if(i<last and small>0)continue;
        if(i>last and big>0)continue;

        if(i==last){
            dp[pos][small][big][last]+=ff(pos+1,small,big,i);
        }else{
            dp[pos][small][big][last]+=ff(pos+1,0,0,i);
        }

        dp[pos][small][big][last]%=mod;
    }

    return dp[pos][small][big][last];
}

int main(){

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin>>n>>m;
    for(int i=1;i<=m;i++){
        cin>>a>>b;

        if(a<b){
            cnt[a+1]++;
            pref[a+1]++; pref[b+1]--;
        }else{
            cnt2[b+1]++;
            pref2[b+1]++; pref2[a+1]--;
        }
    }

    for(int i=1;i<=n;i++){
        pref[i]+=pref[i-1];
        pref2[i]+=pref2[i-1];
    }

    for(int i=0;i<26;i++){
        ans+=ff(2,0,0,i);
        ans%=mod;
    }

    cout<<ans<<"\n";

    return 0;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 20
• Subtask 3: 0 / 29
• Subtask 4: 0 / 32
• Subtask 5: 0 / 11