实验4

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#define N 4
int main() {
    int a[N] = { 1,9,8,4 };
    char b[N] = { '1','9','8','4' };
    int i;

    printf("sizeof(int)=%d\n", sizeof(int));
    printf("sizeof(char)=%d\n", sizeof(char));
    printf("\n");

    for (i = 0; i < N; i++) {
        printf("%p: %d\n", &a[i], a[i]);
    }
    printf("\n");
    printf("a=%p\n", a);
    printf("b=%p\n", b);

    return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#define N 13

int days_of_year(int year, int month, int day);


int main() {
    int year, month, day;
    int days;

    while (scanf("%d%d%d", &year, &month, &day) != EOF) {
        days = days_of_year(year, month, day);
        printf("%4d-%02d-%02d是这一年的第%d天.\n\n", year, month, day, days);
    }

    return 0;
}

int days_of_year(int year, int month, int day) {
    int m[12]={31,28,31,30,31,30,31,31,30,31,30,31};
    int i, days = 0;
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0 && year % 3200 != 0)) {
        m[1] = 29;
    }
    for (i = 0;i < month;i++) {
        days += m[i];
    }
    days += day;
    return days;
}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#define N 5

// 函数声明 
void input(int x[], int n);
void output(int x[], int n);
double average(int x[], int n);
void bubble_sort(int x[], int n);

int main() {
    int scores[N];
    double ave;

    printf("录入%d个分数:\n", N);
    input(scores, N);

    printf("\n输出课程分数: \n");
    output(scores, N);

    printf("\n课程分数处理: 计算均分、排序...\n");
    ave = average(scores, N);
    bubble_sort(scores, N);

    printf("\n输出课程均分: %.2f\n", ave);
    printf("\n输出课程分数(高->低):\n");
    output(scores, N);

    return 0;
}

// 函数定义
// 输入n个整数保存到整型数组x中 
void input(int x[], int n) {
    int i;

    for (i = 0; i < n; ++i)
        scanf("%d", &x[i]);
}

// 输出整型数组x中n个元素 
void output(int x[], int n) {
    int i;

    for (i = 0; i < n; ++i)
        printf("%d ", x[i]);
    printf("\n");
}

// 计算整型数组x中n个元素均值，并返回 
// 补足函数average()实现
// ××× 
double average(int x[], int n) {
    int i, sum = 0;
    for (i = 0;i < n;i++) {
        sum += x[i];
    }
    return sum / n;
}


// 对整型数组x中的n个元素降序排序 
// 补足函数bubble_sort()实现
// ××× 
void bubble_sort(int x[], int n) {
    int i, tem, j;
    for (j = 0;j < n;j++) {
        for (i = 0;i < n - 1;i++) {
            if (x[i] < x[i + 1]) {
                tem = x[i];
                x[i] = x[i + 1];
                x[i + 1] = tem;
            }
        }
    }
}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#define N 100
void dec2n(int x, int n); // 函数声明

int main() {
    int x;

    printf("输入一个十进制整数: ");
    while (scanf("%d", &x) != EOF) {
        dec2n(x, 2);  // 函数调用: 把x转换成二进制输出
        dec2n(x, 8);  // 函数调用: 把x转换成八进制输出
        dec2n(x, 16); // 函数调用: 把x转换成十六进制输出

        printf("\n输入一个十进制整数: ");
    }

    return 0;
}

void dec2n(int x, int n) {
    char a[16] = { '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
    char b[100];
    int i, count = 0;
    while (x != 0) {
        b[++count] = a[x % n];
        x = x / n;
    }
    for (i = count;i > 0;i--) {
        printf("%c", b[i]);
    }
    printf("\n");

}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main() {
    int n, i, j, tem;
    while (scanf("%d", &n) != EOF) {
        for (j = 1;j <= n;j++) {
            tem = 1;
            for (i = 1;i < n;i++) {
                printf("%d ", tem);
                if (tem < j) {
                    tem++;
                }
            }
            printf("%d\n", tem);
        }
    }
    return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <string.h>

#define N 80

int main() {
    char views1[N] = "hey, C, I have not love u yet.";
    char views2[N] = "hey, C, how can I love u?";
    char t[N];

    printf("交换前: \n");
    printf("views1: %s\n", views1);
    printf("views2: %s\n", views2);
    // 交换
    strcpy(t, views1);
    strcpy(views1, views2);
    strcpy(views2, t);

    printf("交换后: \n");
    printf("views1: %s\n", views1);
    printf("views2: %s\n", views2);

    return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <string.h>

#define N 80

int main() {
    char views[2][N] = { "hey, C, I have not love u yet.",
                         "hey, C, how can I love u?" };

    char t[N];

    printf("交换前: \n");
    printf("views1: %s\n", views[0]);
    printf("views2: %s\n", views[1]);

    // 交换
    strcpy(t, views[0]);
    strcpy(views[0], views[1]);
    strcpy(views[1], t);

    printf("交换后: \n");
    printf("views1: %s\n", views[0]);
    printf("views2: %s\n", views[1]);

    return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <string.h>

#define N 5
#define M 20

void bubble_sort(char str[][M], int n); // 函数声明

int main() {
    char name[][M] = { "Bob", "Bill", "Joseph", "Taylor", "George" };
    int i;

    printf("输出初始名单:\n");
    for (i = 0; i < N; i++)
        printf("%s\n", name[i]);

    printf("\n排序中...\n");
    bubble_sort(name, N);  // 函数调用 

    printf("\n按字典序输出名单:\n");
    for (i = 0; i < N; i++)
        printf("%s\n", name[i]);

    return 0;
}

// 函数定义
// 功能：使用冒泡排序算法对二维数组str中的n个字符串按字典序排序
// 补足函数bubble_sort()实现 
// ×××
void bubble_sort(char str[][M], int n) {
    int i, j, k;
    char tem[100][M];
    for (k = 0;k < n;k++) {
        for (i = 0;i < n - 1;i++) {
            if (strcmp(str[i], str[i + 1]) > 0) {
                for (j = 0;j < n;j++) {
                    tem[i][j] = str[i][j];
                    str[i][j] = str[i + 1][j];
                    str[i + 1][j] = tem[i][j];
                }
            }
        }
    }
}