Codeforces Round #828 (Div. 3)1744

https://codeforces.com/contest/1744

A - Number Replacement

#include <bits/stdc++.h>
#define endl '\n'
#define int long long
// #define x first
// #define y second
using namespace std;
// typedef pair<int, int> PII;

void solve() {
    int n;
    cin >> n;
    vector<int> a(n + 1);
    unordered_map<int, char> mp;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    string s;
    cin >> s;
    s = " " + s;
    bool flag = true;
    for (int i = 1; i <= n; i++) {
        char c = s[i];
        if (mp.count(a[i]) == 0) {
            mp[a[i]] = c;
        } else {
            if (mp[a[i]] != c) {
                flag = false;
            }
        }
    }
    if (flag) {
        cout << "YES" << endl;
    } else {
        cout << "NO" << endl;
    }
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(nullptr);
    int _ = 1;
    cin >> _;
    while (_--) {
        solve();
    }
    return 0;
}

B - Even-Odd Increments

#include <bits/stdc++.h>
#define endl '\n'
#define int long long
// #define x first
// #define y second
using namespace std;
// typedef pair<int, int> PII;

void solve() {
    int n, q;
    cin >> n >> q;
    vector<int> a(n + 1);
    int sum = 0;
    int odd = 0, even = 0;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        sum += a[i];
        if (a[i] % 2 == 0)
            even++;
        else
            odd++;
    }
    for (int i = 1; i <= q; i++) {
        int a, b;
        cin >> a >> b;
        if (a == 0) {
            // even += b
            sum += b * even;
            if (b % 2 == 1) {
                odd += even;
                even = 0;
            }
        } else {
            // odd += b
            sum += b * odd;
            if (b % 2 == 1) {
                even += odd;
                odd = 0;
            }
        }
        cout << sum << endl;
    }
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(nullptr);
    int _ = 1;
    cin >> _;
    while (_--) {
        solve();
    }
    return 0;
}

C - Traffic Light

破环为队，方法是2*S

#include <bits/stdc++.h>
#define endl '\n'
#define int long long
// #define x first
// #define y second
using namespace std;

// typedef pair<int, int> PII;

void solve() {
    int n;
    char c;
    string s;
    cin >> n >> c >> s;
    s = s + s;
    int res = -1;
    for (int i = 0; i < 2 * n; i++) {
        // 找到c
        if (s[i] == c) {
            // 找到最近的 g
            int j = i;
            for (; j < 2 * n; j++) {
                if (s[j] == 'g') {
                    // 更新距离
                    res = max(res, j - i);
                    break;
                }
            }
            i = j;
        }
    }
    cout << res << endl;
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(nullptr);
    int _ = 1;
    cin >> _;
    while (_--) {
        solve();
    }
    return 0;
}