Danh mục: 6 BÀI TẬP C++ CHUẨN THI HỌC SINH GIỎI MỚI NHẤT 2026

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    freopen("HCN.INP", "r", stdin);
    freopen("HCN.OUT", "w", stdout);

    double dai, rong;
    if (cin >> dai >> rong) {
        double chu_vi = (dai + rong) * 2;
        double dien_tich = dai * rong;
        cout << fixed << setprecision(2) << chu_vi << " " << dien_tich << endl;
    }
    return 0;
}

#include <iostream>
#include <cmath>
using namespace std;

int main() {
    freopen("SNT.INP", "r", stdin);
    freopen("SNT.OUT", "w", stdout);

    long long n; 
    cin >> n;

    if (n < 2) {
        cout << "NO\n";
        return 0;
    }

    bool la_snt = true;
    long long can_bac_hai = sqrt(n);
    
    for (long long i = 2; i <= can_bac_hai; i++) {
        if (n % i == 0) {
            la_snt = false;
            break;
        }
    }

    if (la_snt) cout << "YES\n";
    else cout << "NO\n";
    
    return 0;
}

#include <iostream>
#include <string>
using namespace std;

int main() {
    freopen("CHUOI.INP", "r", stdin);
    freopen("CHUOI.OUT", "w", stdout);

    string van_ban;
    getline(cin, van_ban); 

    int bien_dem = 0;
    for (int i = 0; i < van_ban.length(); i++) {
        char ky_tu = tolower(van_ban[i]);
        if (ky_tu == 'a' || ky_tu == 'e' || ky_tu == 'i' || ky_tu == 'o' || ky_tu == 'u') {
            bien_dem++;
        }
    }

    cout << bien_dem << endl;
    return 0;
}

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    freopen("SAPXEP.INP", "r", stdin);
    freopen("SAPXEP.OUT", "w", stdout);

    int so_luong;
    if (cin >> so_luong) {
        vector<int> danh_sach(so_luong);
        
        for (int i = 0; i < so_luong; i++) {
            cin >> danh_sach[i];
        }

        sort(danh_sach.begin(), danh_sach.end());

        for (int i = 0; i < so_luong; i++) {
            cout << danh_sach[i] << " ";
        }
        cout << endl;
    }
    return 0;
}

#include <iostream>
#include <cmath>
using namespace std;

class PhanSo {
private:
    long long tu, mau;

    long long tim_ucln(long long a, long long b) {
        a = abs(a); b = abs(b);
        while (b != 0) {
            long long tam = b;
            b = a % b;
            a = tam;
        }
        return a;
    }

public:
    PhanSo(long long t = 0, long long m = 1) {
        tu = t;
        mau = (m == 0) ? 1 : m;
    }

    void toi_gian() {
        long long ucln = tim_ucln(tu, mau);
        tu /= ucln;
        mau /= ucln;
        if (mau < 0) { 
            tu = -tu;
            mau = -mau;
        }
    }

    PhanSo cong(PhanSo doi_tac) {
        PhanSo ket_qua;
        ket_qua.tu = this->tu * doi_tac.mau + doi_tac.tu * this->mau;
        ket_qua.mau = this->mau * doi_tac.mau;
        ket_qua.toi_gian();
        return ket_qua;
    }

    void in_ket_qua() {
        if (mau == 1) cout << tu << endl;
        else cout << tu << "/" << mau << endl;
    }
};

int main() {
    freopen("PHANSO.INP", "r", stdin);
    freopen("PHANSO.OUT", "w", stdout);

    long long t1, m1, t2, m2;
    if (cin >> t1 >> m1 >> t2 >> m2) {
        PhanSo ps1(t1, m1), ps2(t2, m2);
        PhanSo tong = ps1.cong(ps2);
        tong.in_ket_qua();
    }
    return 0;
}

#include <iostream>
#include <map>
using namespace std;

int main() {
    freopen("TIMSO.INP", "r", stdin);
    freopen("TIMSO.OUT", "w", stdout);

    int n;
    if (cin >> n) {
        map<int, int> bo_dem;
        int so_nhap;
        
        for (int i = 0; i < n; i++) {
            cin >> so_nhap;
            bo_dem[so_nhap]++; 
        }

        int max_tan_suat = 0;
        int gia_tri_toi_uu = 0;

        for (auto phan_tu : bo_dem) {
            if (phan_tu.second > max_tan_suat) {
                max_tan_suat = phan_tu.second;
                gia_tri_toi_uu = phan_tu.first;
            }
        }

        cout << gia_tri_toi_uu << " " << max_tan_suat << endl;
    }
    return 0;
}