22年+21年 计算机能力挑战赛初赛C语言程序题 题解

#include<stdio.h>
int  x=1;
int f(int  a)
{   static int  x=2;
    int  n=0;
   if(a%2)
         { static int  x=3;n+=x++;  }
   else  
         { static int  x=5;n+=x++;  }
    return  n+x++;
 } 
void  main()
{   int  sum=x,i;
    for(i=0;i<4;i++) 
         sum+=f(i); 
    printf("%d",sum);
}

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
// 比较函数，用于qsort排序
int compare(const void *a, const void *b) {
    return (*(char*)a - *(char*)b);
}
int main() {
    int x, y;
    char str[25];
    // 读取输入
    scanf("%d %d", &x, &y);
    // 将两个整数转换为字符串
    sprintf(str, "%d%d", x, y);
    // 对字符串进行排序
    qsort(str, strlen(str), sizeof(char), compare);
    // 输出重新组合后的最小数
    printf("%s\n", str);
    return 0;
}

#include <stdio.h>
#include <stdbool.h>
// 判断素数
bool isPrime(int n) {
    if (n <= 1) {
        return false;
    }
    for (int i = 2; i * i <= n; i++) {
        if (n % i == 0) {
            return false;
        }
    }
    return true;
}
// 判断是否为对称数
bool isSymmetric(int n) {
    int reverse = 0, original = n;
    while (n > 0) {
        reverse = reverse * 10 + n % 10;
        n /= 10;
    }
    return original == reverse;
}
// 统计满足条件的数字个数
int countNumbers(int N) {
    int count = 0;
    for (int i = 1; i <= N; i++) {
        if (isPrime(i) && isSymmetric(i)) {
            int sumOfDigits = 0, num = i;
            while (num > 0) {
                sumOfDigits += num % 10;
                num /= 10;
            }
            if (sumOfDigits % 7 == 0) {
                count++;
            }
        }
    }
    return count;
}
int main() {
    int N;
    scanf("%d", &N);
    int result = countNumbers(N);
    printf("%d\n", result);
    return 0;
}

#include <stdio.h>
#include <stdbool.h>
// 判断一个数是否是素数
bool isPrime(int n) {
    if (n <= 1) {
        return false;
    }
    for (int i = 2; i * i <= n; i++) {
        if (n % i == 0) {
            return false;
        }
    }
    return true;
}
// 判断一个数是否是对称的数
bool isPalindrome(int n) {
    int temp = n;
    int reversed = 0;
    
    while (temp != 0) {
        reversed = reversed * 10 + temp % 10;
        temp /= 10;
    }
    
    return reversed == n;
}
// 计算一个数的各位数字之和
int sumOfDigits(int n) {
    int sum = 0;
    
    while (n != 0) {
        sum += n % 10;
        n /= 10;
    }
    
    return sum;
}
int main() {
    int N;
    int count = 0;
    
    // 读取输入
    scanf("%d", &N);
    
    // 遍历从1到N的所有数字
    for (int i = 1; i <= N; i++) {
        int conditionCount = 0;
        
        if (isPrime(i)) {
            conditionCount++;
        }
        
        if (isPalindrome(i)) {
            conditionCount++;
        }
        
        if (sumOfDigits(i) % 7 == 0) {
            conditionCount++;
        }
        
        if (conditionCount >= 2) {
            count++;
        }
    }
    
    // 输出满足条件的个数
    printf("%d\n", count);
    
    return 0;
}

#include <stdio.h>
#include <string.h>
struct Student {
    char name[100];
    int chinese;
    int math;
    int english;
    int total;
};
int main() {
    int n;
    printf("请输入学生人数：");
    scanf("%d", &n);
    struct Student students[n];
    // 输入每个学生的信息
    for (int i = 0; i < n; i++) {
        printf("请输入第%d个学生的姓名、语文成绩、数学成绩和英语成绩：", i+1);
        scanf("%s %d %d %d", students[i].name, &students[i].chinese, &students[i].math, &students[i].english);
        students[i].total = students[i].chinese + students[i].math + students[i].english;
    }
    // 找到各科目和总分最低的学生
    int chinese_min = students[0].chinese;
    int math_min = students[0].math;
    int english_min = students[0].english;
    int total_min = students[0].total;
    for (int i = 1; i < n; i++) {
        if (students[i].chinese < chinese_min) {
            chinese_min = students[i].chinese;
        }
        if (students[i].math < math_min) {
            math_min = students[i].math;
        }
        if (students[i].english < english_min) {
            english_min = students[i].english;
        }
        if (students[i].total < total_min) {
            total_min = students[i].total;
        }
    }
    // 输出语文最低成绩的学生
    printf("lower chinese:\n");
    for (int i = 0; i < n; i++) {
        if (students[i].chinese == chinese_min) {
            printf("%s(%d)\n", students[i].name, students[i].chinese);
        }
    }
    // 输出数学最低成绩的学生
    printf("lower math:\n");
    for (int i = 0; i < n; i++) {
        if (students[i].math == math_min) {
            printf("%s(%d)\n", students[i].name, students[i].math);
        }
    }
    // 输出英语最低成绩的学生
    printf("lower english:\n");
    for (int i = 0; i < n; i++) {
        if (students[i].english == english_min) {
            printf("%s(%d)\n", students[i].name, students[i].english);
        }
    }
    // 输出总分最低的学生
    printf("lower score:\n");
    for (int i = 0; i < n; i++) {
        if (students[i].total == total_min) {
            printf("%s(%d)\n", students[i].name, students[i].total);
        }
    }
    return 0;
}