Educational Codeforces Round 123

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A:Doors and Keys

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#include <iostream>
#include <bits/stdc++.h>
#include <map>
#include <algorithm>
using namespace std;

int main()
{
    int t;
    cin >> t;
    while(t--) {
        string s;
        map<char, bool> vis;
        cin >> s;
        int flag = 0;
        for (int i = 0; i < s.size(); i++) {
            if(s[i] <= 'Z' && s[i] >= 'A') {
                if(!vis[s[i] + 32]) {
                    flag = 1;
                    break;
                } 
            }
            vis[s[i]] = true;
        }
        if(flag || vis.size() != 6) {
            cout << "NO" << endl;
        } else {
            cout << "YES" << endl;
        }
    }
    return 0;
}

B:Anti-Fibonacci Permutation

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#include <bits/stdc++.h>

using namespace std;

//如果是1在的位置，后面两者需要调换
void print(int x, int n) {
    vector<int>vec;
    int t = n;
    while(t--) {
        vec.push_back(x%n);
        x++;
    }
    for(int i = 0; i < vec.size(); i++) {
        if(vec[i] == 0 && i < vec.size() - 2) {
            swap(vec[i + 1], vec[i + 2]);
        } 
        cout << vec[i] + 1 << " ";
    }
    cout << endl;
}

int main()
{
    int t;
    cin >> t;
    while(t--) {
        int n;
        cin >> n;
        for(int i = 1; i <= n; i++) {
            print(i, n);
        }
    }
    return 0;
}

C:Increase Subarray Sums

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#include <bits/stdc++.h>

using namespace std;
#define ll long long 

const int maxn = 5100;
const int mod = 1000000007;

ll a[maxn];
ll sum[maxn];
int main()
{ 
    int t;
    cin >> t;
    while(t--) {  
        int n, x;
        cin >> n >> x;
        for (int i = 1; i <= n; i++) {
            cin >> a[i];
            a[i] += a[i-1];
            sum[i] = min(sum[i-1], a[i]);
        }
        long long ans = 0;
        for (int i=0; i<=n; i++) {
            for (int j=i; j<=n; j++) {
                ans = max(ans, a[j] - sum[j-i] + i*x);
            }
            cout << ans << " ";
        }
        cout << endl;
    }
    return 0;
}