你最好别复制 : )

T1

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

int a[100005];
bool good[100005];

int main()
{
    freopen("discuss.in", "r", stdin);
    freopen("discuss.out", "w", stdout);
    int t, n;
    cin >> t;
    while (t--)
    {
        cin >> n;
        memset(good, 0, sizeof(good));
        for (int i = 1; i <= n; i++)
        {
            cin >> a[i];
            if (i > 1 && a[i] == a[i - 1] || i > 2 and a[i] == a[i - 2])
                good[a[i]] = 1;
        }

        bool at_least_one = 0;
        for (int i = 1; i <= n; i++)
        {
            if (good[i])
            {
                at_least_one = 1;
                cout << i << " ";
            }
        }
        if (!at_least_one)
            cout << -1;
        cout << '\n';
    }
}

T2

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

int dp[32][32];
int n, m;

int main()
{
    freopen("ball.in", "r", stdin);
    freopen("ball.out", "w", stdout);
    cin >> n >> m;
    dp[n][1] = 1;
    dp[2][1] = 1;
    for (int j = 2; j <= m; j++)
    {
        for (int i = 1; i <= n; i++)
        {
            int l = i - 1, r = i + 1;
            if (l == 0)
                l = n;
            if (r == n + 1)
                r = 1;
            dp[i][j] = dp[l][j - 1] + dp[r][j - 1];
        }
    }
    cout << dp[1][m];
    return 0;
}

T3

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

#define ll long long

const ll N = (ll)2e5 + 5;

ll mns, add, n, a[N];

int main()
{
    freopen("land.in", "r", stdin);
    freopen("land.out", "w", stdout);
    cin >> n;
    for (int i = 1; i <= n; i++)
        scanf("%lld", &a[i]);
    for (int i = 1; i <= n; i++)
    {
        ll tmp = a[i] - mns + add - a[i - 1];
        if (tmp > 0)
            mns += tmp;
        else
            add += -tmp;
    }
    cout << mns + add;
    return 0;
}

T4

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

int main()
{
    freopen("jump.in","r",stdin);
    freopen("jump.out","w",stdout);
    int n, x;
    cin >> n >> x;
    vector<pair<int, int>> pad(n + 1);
    vector<bool> vis(n + 1);
    for (int i = 1; i <= n; ++i)
        cin >> pad[i].first >> pad[i].second;
    int dir = 1, power = 1, ans = 0;
    for (int reps = 0; reps < 5000000 && 1 <= x && x <= n; ++reps)
    {
        if (pad[x].first == 1 && power >= pad[x].second && !vis[x])
        {
            vis[x] = true;
            ++ans;
        }
        if (pad[x].first == 0)
        {
            dir *= -1;
            power += pad[x].second;
        }
        x += dir * power;
    }
    cout << ans << "\n";
    return 0;
}