link

A

。

#include "bits/stdc++.h"

using namespace std;

void solve() {
    int n;
    string s;
    cin >> n >> s;
  
    vector<int> cnt(26);
    for (int i = 0; i < n; i++) {
        cnt[s[i] - 'a']++;
    }
    sort(cnt.begin(), cnt.end());

    for (int i = 0; i < 26; i++) {
        if (i > 0 && cnt[i] && cnt[i - 1] && cnt[i] != cnt[i - 1] + 1) {
            cout << "NO\n";
            return;
        }
    }
    cout << "YES\n";
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}

B

。

#include "bits/stdc++.h"

using namespace std;

void solve() {
    int x;
    cin >> x;

    if (x < 4) {
        cout << "-1\n";
    } else {
        cout << (x % 2 ? 1 : 2) << '\n';
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}

C

打表。

。

#include "bits/stdc++.h"

using namespace std;

void solve() {
    int n;
    cin >> n;
    vector<int> a(n);
    iota(a.begin(), a.end(), 1);

    if (n == 2) {
        cout << "-1\n";
        return;
    }

    if (!(n % 2)) {
        swap(a[n - 1] , a[n - 2]);
    }
  
    for (int i = 0; i < n; i++) {
        cout << a[i] << " \n"[i == n - 1];
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}

D

。

#include "bits/stdc++.h"

using namespace std;

void solve() {
    int n, m;
    cin >> n >> m;
    vector<int> a(n), b(m);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    for (int i = 0; i < m; i++) {
        cin >> b[i];
    }

    vector<pair<int, int>> pa, pb;
    for (int i = 0; i < n; ) {
        int j = i;
        while (j < n && a[j] == a[i]) {
            j++;
        }
        pa.emplace_back(a[i], j - i);
        i = j;
    }
    for (int i = 0; i < m; ) {
        int j = i;
        while (j < m && b[j] == b[i]) {
            j++;
        }
        pb.emplace_back(b[i], j - i);
        i = j;
    }

    if (pa.size() != pb.size()) {
        cout << "-1\n";
        return;
    }

    int k = pa.size();
    int ans = 0;
    for (int i = 0; i < k; i++) {
        if (pa[i].first != pb[i].first) { 
            cout << "-1\n";
            return;
        }
        int ca = pa[i].second, cb = pb[i].second;
        if (cb < ca) { 
            cout << "-1\n";
            return;
        }
        int r = 0, c = ca;
        while (c < cb) {
            c <<= 1;
            r++;
        }
        ans = max(ans, r);
    }
    cout << ans << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}

E

#include "bits/stdc++.h"

using namespace std;
using i64 = int64_t;

void solve() {
    int n;
    cin >> n;
    vector<i64> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }

    auto v = a;
    sort(v.begin(), v.end());
    v.erase(unique(v.begin(), v.end()), v.end());

    unordered_map<i64, int> mp;
    for (int i = 0; i < n; i++) {
        if (!mp.count(a[i])) {
            mp[a[i]] = i + 1;
        }
    }

    unordered_map<i64, int> ans;
    int m = v.size();
    for (int i = 0; i < m; i++) {
        int j = i - 1;
        while (j >= 0) {
            if (v[i] % v[j]) {
                ans[v[i]] = mp[v[j]];
                break;
            }
            j--;
        }
        if (j < 0) {
            ans[v[i]] = -1;
        }
    }
    
    for (int i = 0; i < n; i++) {
        cout << ans[a[i]] << " \n"[i == n - 1];
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t;
    cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}