双指针

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#include <bits/stdc++.h>
using namespace std;
using i64 = long long;


void solve() {
    i64 n;
    cin >> n;
    i64 N = 1e5 + 10;
    vector<i64> nums(N, 0);
    vector<i64> flag(N, 0);
    for (i64 i = 1; i <= n; i++) cin >> nums[i];

    i64 ans = 0;
    for (i64 i = 1, j = 1; i <= n; ++i) {
        flag[nums[i]] ++;
        while(j <= i && flag[nums[i]] > 1 ) {
            flag[nums[j]] --; 
            j ++;
        }
        ans = max(ans,i - j + 1);
    }
    cout << ans << "\n";
}

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

    solve();

    return 0;
}

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void solve() {
    
    i64 n, m, x;
    cin >> n >> m >> x;

    vector<i64> a(n + 1, 0);
    vector<i64> b(m + 1, 0);

    for(i64 i = 1; i <= n; i++) cin >> a[i];
    for(i64 i = 1; i <= m; i++) cin >> b[i];

    i64 l = 1, r = m;
    while(l <= n && r > 0) {
        if(a[l] > x) break;
        if(a[l] + b[r] > x) r--;
        if(a[l] + b[r] == x) {
            cout << l - 1 << " " << r - 1 << '\n';
            l++;
        }
        if(a[l] + b[r] < x) l++;
    }
}

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

    solve();

    return 0;
}

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#include <bits/stdc++.h>
using namespace std;
using i64 = long long;


void solve() {
    
    i64 n, m;
    cin >> n >> m;

    vector<i64> a(n + 1, 0);
    vector<i64> b(m + 1, 0);

    for(i64 i = 1; i <= n; i++) cin >> a[i];
    for(i64 i = 1; i <= m; i++) cin >> b[i];

    i64 l = 1, r = 1;
    while(l <= n && r <= m) {
        if(a[l] == b[r]) l++;
        r++;
    }
    if(l == n + 1) cout << "Yes\n";
    else cout << "No\n";
}

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

    solve();
    return 0;
}