Codeforces Round 888 (Div. 3)记录

A. Escalator Conversations

#include<cstdio>
#include<algorithm>
#include<cmath>
#include<vector>
#include<string.h>
#include<set>
#include<string>
#include<map>
#include<iostream>
#include<queue>
#include<unordered_set>
#include<stdlib.h>
#include<sstream>
#include<iomanip>
typedef long long ll;
using namespace std;
const int Mod=1e9+7;
const int N=2e5+7;
int T;
int n,q,m;
int main()
{
    cin >> T;
    while(T--){
        int k,H,h[55];
        cin>>n>>m>>k>>H;
        int cnt=0;
        for(int i=0;i<n;i++)
        {
            int dif=0;
            cin>>h[i];
            dif=abs(H-h[i]);
            if(dif%k==0&&dif/k<m&&H!=h[i])
            {
                cnt++;
            }
        }
        cout<<cnt<<endl;
    }
    system("pause");
    return 0;
}

B - Parity Sort

#include<cstdio>
#include<algorithm>
#include<cmath>
#include<vector>
#include<string.h>
#include<set>
#include<string>
#include<map>
#include<iostream>
#include<queue>
#include<unordered_set>
#include<stdlib.h>
#include<sstream>
#include<iomanip>
typedef long long ll;
using namespace std;
const int Mod=1e9+7;
const int N=2e5+7;
int T;
int n,q,m;
int main()
{
    cin >> T;
    while(T--){
       cin>>n;
       int a[N],b[N];
       map<int,int> mp;
       for(int i=0;i<n;i++)
       {
            cin>>a[i];
            b[i] = a[i];
            mp[a[i]]=i;
       }
       sort(a,a+n);
       int flag=0;
       for(int i=0;i<n;i++)
       {
            if(b[i]!=a[i])
            {
                int f=mp[a[i]];
                
                if((b[i]%2==0&&b[f]%2==0)||(b[i]%2!=0&&b[f]%2!=0))
                {

                }
                else
                {
                    cout<<"NO"<<endl;
                    flag=1;
                    break;
                }
            }
       }
       if(flag==0)
       {
        cout<<"YES"<<endl;
       }
    }
    system("pause");
    return 0;
}

C - Tiles Comeback

#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
const int N = 2e5 + 7;
int T;
int n, q, m;
int main()
{
    int x,x1,x2;
    cin >> T;
    while (T--)
    {
        int k;
        cin >> n >> k;
        int c[N];
        map<int, int> ha;
        for (int i = 1; i <= n; i++)
        {
            cin >> c[i];
            ha[c[i]]++;
        }
        if(c[1] == c[n]){
            int flag1 = 0;
            for(int i = 1;i <= ha[c[1]];i++){
                if(i >= k){
                    if(i % k == 0){
                        flag1 = 1;
                        cout << "YES" << endl;
                        break;
                    }
                }
            }
            if(!flag1)cout << "NO" << endl;
        }
        else{
            if(ha[c[1]] < k || ha[c[n]] < k){
                cout << "NO" << endl;
            }
            else{
                int sum = 0,i = 1;
                while(sum < k && i <= n){
                    if(c[i] == c[1]){
                        sum++;
                    }
                    i++;
                }
                int sum1 = 0,i1 = n;
                while(sum1 < k && i1 >= i){
                    if(c[i1] == c[n]){
                        sum1++;
                    }
                    i1--;
                }
                if(sum1 >= k && sum >= k){
                    cout << "YES" << endl;
                }
                else cout << "NO" << endl;
            }
        }
    }
    system("pause");
    return 0;
}