C++基础题

水仙花数

#include <iostream>
using namespace std;
int main() {
    cout << "3位水仙花数：" << endl;
    for (int num = 100; num <= 999; num++) {
        int digit1 = num / 100;     // 百位数字
        int digit2 = (num / 10) % 10;  // 十位数字
        int digit3 = num % 10;      // 个位数字
        if (num == (digit1 * digit1 * digit1 + digit2 * digit2 * digit2 + digit3 * digit3 * digit3)) {
            cout << num << " ";
        }
    }
    cout << endl;
    return 0;
}

五角星数

【问题描述】
求出所有的五角星数，所谓五角星数是指它的各个数位上数字的五次方等于它本身的数。例如54748=55555+
44444+77777+44444+88888
【输出格式】
一行所有的五角星数，以空格隔开。

#include <iostream>
#include <cmath>
bool isPentagonalNumber(int num) {
    int originalNum = num;
    int sum = 0;
    while (num > 0) {
        int digit = num % 10;
        sum += pow(digit, 5);
        num /= 10;
    }
    return (sum == originalNum);
}

void printAllPentagonalNumbers() {
    cout << "所有的五角星数：" << std::endl;

    for (int num = 0; num <= 99999; num++) {
        if (isPentagonalNumber(num)) {
            cout << num << " ";
        }
    }
    cout << std::endl;
}
int main() {
    printAllPentagonalNumbers();
    return 0;
}

数字图形三角形一

#include <iostream>
int main() {
    int n;
    cout << "Enter the number of rows: ";
    cin >> n;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= i; j++) {
            cout << i;
        }
        cout<<endl;
    }
    return 0;
}

统计15个同学中成绩为100分的人数

#include <iostream>
int main() {
    const int numStudents = 15;
    int scores[numStudents];
    cout << "Enter the scores of " << numStudents << " students:" << endl;
    // 输入15个整数作为同学们的成绩
    for (int i = 0; i < numStudents; i++) {
        cin >> scores[i];
    }
    int count = 0;
    // 统计成绩为100分的人数
    for (int i = 0; i < numStudents; i++) {
        if (scores[i] == 100) {
            count++;
        }
    }
    cout << "Number of students with a score of 100: " << count << endl;
    return 0;
}