实验3

#include <stdio.h>

char score_to_grade(int score);  

int main() {
    int score;
    char grade;

    while(scanf("%d", &score) != EOF) {
        grade = score_to_grade(score); 
        printf("分数: %d, 等级: %c\n\n", score, grade);
    }

    return 0;
}

char score_to_grade(int score) {
    char ans;

    switch(score/10) {
    case 10:
    case 9:   ans = 'A'; break;
    case 8:   ans = 'B'; break;
    case 7:   ans = 'C'; break;
    case 6:   ans = 'D'; break;
    default:  ans = 'E';
    }

    return ans;
}

　　

 

将数转换为等级（A，B，C，D，E）。

   形参类型：int

   返回值类型：char

 ans = "A" 应改为 ans = 'A'

   缺指令 选择无法正确执行

2

#include <stdio.h>
int sum_digits(int n);  // 函数声明
int main() {
    int n;
    int ans;
    while (printf("Enter n: "), scanf("%d", &n) != EOF) {
        ans = sum_digits(n);    // 函数调用
        printf("n = %d, ans = %d\n\n", n, ans);
    }
    return 0;
}
// 函数定义
int sum_digits(int n) {
    int ans = 0;
    while (n != 0) {
        ans += n % 10;
        n /= 10;
    }
    return ans;
}

　　

1.计算并返回一个整数n各位数字之和

2.能够实现相同的输出结果

3.

#include <stdio.h>

int power(int x, int n);

int main() {
    int x, n;
    int ans;

    while(printf("Enter x and n: "), scanf("%d%d", &x, &n) != EOF) {
        ans = power(x, n); 
        printf("n = %d, ans = %d\n\n", n, ans);
    }
    
    return 0;
}

int power(int x, int n) {
    int t;

    if(n == 0)
       return 1;
    else if(n % 2)
       return x * power(x, n-1);
    else {
       t = power(x, n/2);
       return t*t;
    }
}

　　

4.

#include <stdio.h>
#include <stdlib.h>

int classify_triangle(int a, int b, int c);

int main()
{
    int a, b, c, ans;
    while (scanf("%d%d%d", &a, &b, &c) != EOF)
    {
        ans = classify_triangle(a, b, c);
        switch (ans)
        {
            case 0: printf("不能构成三角形\n"); break;
            case 1: printf("普通三角形\n"); break;
            case 2: printf("等边三角形\n"); break;
            case 3: printf("等腰三角形\n"); break;
            case 4: printf("直角三角形\n"); break;
        }
    }
    system("pause");
   
    return 0;
}

int classify_triangle(int a, int b, int c)
{
    if (a + b <= c || a + c <= b || b + c <= a)
        return 0;
    else if (a == b && b == c)
        return 2;
    else if (a == b || a == c || b == c)
        return 3;
    else if (a*a + b*b == c*c || a*a + c*c == b*b || b*b + c*c == a*a)
        return 4;
    else 
        return 1;
}

　　

5.

#include <stdio.h>

int func(int n, int m);

int main() {
    int n, m;
    int ans;

    while (scanf("%d%d", &n, &m) != EOF) {
        ans = func(n, m);
        printf("n = %d, m = %d, ans = %d\n\n", n, m, ans);
    }

    return 0;
}

int func(int n, int m) {
    if (m < 0 || m > n) return 0;
    if (m == 0 || m == n) return 1;
    if (m > n - m) m = n - m;
    int result = 1;
    for (int i = 1; i <= m; i++) {
        result = result * (n - m + i) / i;
    }
    return result;
}

6.

#include <stdio.h>
int gcd(int a,int b,int c);
int main(){
    int a,b,c;
    int ans;
    
    while(scanf("%d%d%d",&a,&b,&c)!=EOF){
        ans=gcd(a,b,c);
        printf("最大公约数：%d\n\n",ans);
    }
    return 0;
}
int gcd(int a,int b,int c){
    int min=a;
    if(min>b){
        min=b;
    }
    if(min>c){
        min=c;
    }
    
    for(int i=min;i>=1;i--){
        if(a%i==0&&b%i==0&&c%i==0){
            return i;
        }
} }

7.

#include <stdio.h>
#include <stdlib.h>

void print_charman(int n);

int main(){
    int n;
    printf("Enter n:");
    scanf("%d", &n); 
    print_charman(n);
    return 0;
}

void print_charman(int n){
    int i, j, k;
    
    for(k = n; k >= 1; k--){
        int cnt = 2 * k - 1;
        int space = n - k;  
        
        
        for(i = 0; i < space; i++){
            printf("\t"); 
        }
        for(i = 0; i < cnt; i++){
            printf(" O\t");
        }
        printf("\n");
        
        for(i = 0; i < space; i++){
            printf("\t");
        }
        for(i = 0; i < cnt; i++){
            printf("<H>\t");
        }
        printf("\n");
        
        for(i = 0; i < space; i++){
            printf("\t");
        }
        for(i = 0; i < cnt; i++){
            printf("I I\t");
        }
        printf("\n");
    }
}