A

签到

#include<bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
#define lowbit(x) ((x)&(-(x)))
#define foru(i,begin,end) for(i=begin;i<=end;i++)
#define ford(i,begin,end) for(i=begin;i>=end;i--)
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define maxheap(x) priority_queue<x,vector<x>,less<x> > 
#define minheap(x) priority_queue<x,vector<x>,greater<x> > 
#define endl '\n'
typedef pair<int, int> PII;
typedef pair<long long, long long> PLL;
typedef long long ll;
typedef unsigned long long ull;
//#define mod 1000000009
//#define mod 1000000007
int a[100005];
int main()
{
    int n,m;
    cin>>n>>m;
    int i;
    for(i=1;i<=n;i++) cin>>a[i];
    ll res=0;
    for(i=1;i<=m;i++)
    {
        int x;
        cin>>x;
        res+=a[x];
    }
    cout<<res<<endl;
    return 0;
}

B

签到

#include<bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
#define lowbit(x) ((x)&(-(x)))
#define foru(i,begin,end) for(i=begin;i<=end;i++)
#define ford(i,begin,end) for(i=begin;i>=end;i--)
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define maxheap(x) priority_queue<x,vector<x>,less<x> > 
#define minheap(x) priority_queue<x,vector<x>,greater<x> > 
#define endl '\n'
typedef pair<int, int> PII;
typedef pair<long long, long long> PLL;
typedef long long ll;
typedef unsigned long long ull;
//#define mod 1000000009
//#define mod 1000000007

int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int x,y;
        cin>>x>>y;
        if(x%3!=y%3)
        {
            cout<<"No"<<endl;
        }
        else
        cout<<"Yes"<<endl;
    }

    return 0;
}

C

特判全为 的情况，能取 时尽量取 ，否则取最小的数。

#include<bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
#define lowbit(x) ((x)&(-(x)))
#define foru(i,begin,end) for(i=begin;i<=end;i++)
#define ford(i,begin,end) for(i=begin;i>=end;i--)
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define maxheap(x) priority_queue<x,vector<x>,less<x> > 
#define minheap(x) priority_queue<x,vector<x>,greater<x> > 
#define endl '\n'
typedef pair<int, int> PII;
typedef pair<long long, long long> PLL;
typedef long long ll;
typedef unsigned long long ull;
//#define mod 1000000009
//#define mod 1000000007
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        string s;
        cin>>s;
        string ans;
        int i;
        if(s.size()==1)
        {
            cout<<'1'<<endl;
            continue;
        }
        for(i=0;i<s.size();i++) ans.push_back('0');
        string tmp=ans;
        for(i=0;i<s.size();i++)
        {
            if(s[i]=='0')
            {
                ans[i]='1';
            }
        }
        if(ans!=tmp)
        {
            goto A;
        }
        for(i=s.size()-1;i>=0;i--)
        {
            if(s[i]=='0') continue;
            if(s[i]=='1')
            {
                ans[i]='2';
            }
            else ans[i]='1';
            break;
        }
        if(tmp==ans)
        {
            cout<<1<<endl;
            continue;
        }
        A:
        int flag=0;
        for(auto i:ans)
        {
            if(!flag&&i=='0') continue;
            if(i!='0') flag=1;
            cout<<i;
        }
        cout<<endl;
    }

    return 0;
}

D

状态压缩暴力

#include<bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
#define lowbit(x) ((x)&(-(x)))
#define foru(i,begin,end) for(i=begin;i<=end;i++)
#define ford(i,begin,end) for(i=begin;i>=end;i--)
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define maxheap(x) priority_queue<x,vector<x>,less<x> > 
#define minheap(x) priority_queue<x,vector<x>,greater<x> > 
#define endl '\n'
typedef pair<int, int> PII;
typedef pair<long long, long long> PLL;
typedef long long ll;
typedef unsigned long long ull;
//#define mod 1000000009
//#define mod 1000000007
#define mod 998244353
struct node
{
    int l,r;
}a[15];
int yes[15];
int n,m;
ll dp[1<<12];
ll tmp[100005];
ll ans[100005];
bool check(int x)
{
    memset(yes,0,sizeof(yes));
    int i,j;
    for(i=0;i<m;i++)
    {
        if(x&(1<<i)) yes[i+1]=1;
    }
    for(i=0;i<=n;i++) tmp[i]=ans[i]=0;
    for(i=1;i<=m;i++)
    {
        if(yes[i]) tmp[a[i].l]++,tmp[a[i].r+1]--;
    }
    for(i=1;i<=n;i++)
    {
        ans[i]=ans[i-1]+tmp[i];
        if(ans[i]<2) return 0;
    }
    return 1;
}
int main()
{
    
    cin>>n>>m;
    int i,j;
    for(i=1;i<=m;i++)
    {
        cin>>a[i].l>>a[i].r;
    }
    for(i=0;i<1<<m;i++)
    {
        if(dp[i])
        {
            continue;
        }
        else
        {
            if(check(i))
            {
                dp[i]=1;
            }
        }
    }
    ll res=0;
    for(i=1;i<1<<m;i++)
    {
        if(dp[i]) res++;
        res%=mod;
    }
    cout<<res;
    return 0;
}

E

由于 很小，每次询问枚举最后一个 问题的序号，用大顶堆维护最小值即可。

#include<bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
#define lowbit(x) ((x)&(-(x)))
#define foru(i,begin,end) for(i=begin;i<=end;i++)
#define ford(i,begin,end) for(i=begin;i>=end;i--)
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define maxheap(x) priority_queue<x,vector<x>,less<x> > 
#define minheap(x) priority_queue<x,vector<x>,greater<x> > 
#define endl '\n'
typedef pair<int, int> PII;
typedef pair<long long, long long> PLL;
typedef long long ll;
typedef unsigned long long ull;
//#define mod 1000000009
//#define mod 1000000007
ll a[100005],b[100005];
ll sum[100005];
int main()
{
    int n,q;
    cin>>n>>q;
    int i;
    for(i=1;i<=n;i++) cin>>a[i];
    for(i=1;i<=n;i++) cin>>b[i];
    for(i=1;i<=n;i++) sum[i]=sum[i-1]+a[i];
    while(q--)
    {
        int x;
        cin>>x;
        ll res=0;
        maxheap(int) q;
        for(i=1;i<=x;i++)
        {
            q.push(b[i]);
            res+=b[i];
        }
        ll now=res;
        res+=sum[x];
        for(i=x+1;i<=n;i++)
        {
            ll tmp=sum[i];
            if(b[i]<q.top())
            {
                now-=q.top();
                q.pop();
                q.push(b[i]);
                now+=b[i];
                tmp+=now;
                res=min(res,tmp);
            }
        }
        cout<<res<<endl;

    }
    return 0;
}