2015年海淀区信息学竞赛小学组详细答案

傷城~ 2022-04-24 02:20 160阅读 0赞

# 1 成绩统计 #

#include <iostream>
    using namespace std;
    
    int main()
    {
        int n;
        cin >> n;
        int cnt1 = 0, cnt2 = 0, cnt3 = 0, cnt4 = 0;
        int a[n];
        for(int i = 0; i < n; i++)
        {
            cin >> a[i];
            if(a[i] >= 90 && a[i] <= 100)
            {
                cnt1++;
            }
            else if(a[i] >= 80 && a[i] <= 89)
            {
                cnt2++;
            }
            else if(a[i] >= 60 && a[i] <= 79)
            {
                cnt3++;
            }
            else
            {
                cnt4++;
            }
        }
    
        cout << "You " << cnt1 << endl;
        cout << "Liang " << cnt2 << endl;
        cout << "Zhong " << cnt3 << endl;
        cout << "Cha " << cnt4 << endl;
    
        return 0;
    }

# 2 打印图形 #

#include <iostream>
    using namespace std;
    
    int main()
    {
        int n;
        cin >> n;
        for(int i = 1; i <= 2 * n - 1; i++)
        {
            int j = (i > n) ? 2 * n - i : i;
            for(int k = 1; k < j; k++)
            {
                cout << ' ';
            }
    
            char c;
            for(c = 'A' + j - 1; c < 'A' + n; c++)
            {
                cout << c;
            }
            for(c = c - 2; c >= 'A' + j - 1; c--)
            {
                cout << c;
            }
    
            cout << endl;
        }
    
        return 0;
    }

# 3 数值计算 #

#include<bits/stdc++.h>
    using namespace std;
    
    bool isprime(int a)
    {
        if(a == 1)
        {
            return false;
        }
    
        for(int i = 2; i <= sqrt(a); i++)
        {
            if(a % i == 0)
            {
                return false;
            }
        }
    
        return true;
    }
    
    int main()
    {
        int l, r, sum = 0;
        cin >> l >> r;
        for(int i = l; i <= r; i++)
        {
            if(isprime(i) && 
               sqrt(i / 100) - (int)sqrt(i / 100) == 0 && 
               sqrt(i % 100) - (int)sqrt(i % 100) == 0)
            {
                cout << i << endl;
                sum++;
            }
        }
    
        cout << sum << endl;
        return 0;
    }

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[.jpg]: /images/20220221/43f680d47a9d4a75bb8d305729393a73.png