实验四

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

1.连续存放，四个

2.连续存放，一个

3.一样

#include<stdio.h>
#define N 2
#define M 4
int main()
{
    int a[N][M] = {{ 1,9,8,4 }, { 2,0,2,2 }};
    char b[N][M] = { {'1','9','8','4'},{'2','0','2','2'} };
    int i, j;
    for (i = 0; i < N; ++i)
        for (j = 0; j < M; ++j)
            printf("%pP:%d\n", &a[i][j], a[i][j]);
    printf("\n");
    for (i = 0; i < N; ++i)
        for (j = 0; j < M; ++j)
            printf("%p:%c\n", &b[i][j], b[i][j]);
    return 0;
}

1.连续，四个

2.连续，一个

#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_s("%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", year, month, day, days);
    }

    return 0;
}
int days_of_year(int year, int month, int day)
{
    int sum = 0, i;
    for(i=1;i<month;i++)
    {
        if (i==1|| i == 3|| i == 5 || i == 7 || i == 8 || i == 10 || i == 12)
            sum = sum + 31;
        else if (i == 2)
        {
            if (year % 4 == 0 && year % 100 != 0)
                sum = sum + 29;
            else
                sum = sum + 28;
        }
        else
            sum = sum + 30;
    }
    sum = sum + day;
    return sum;
}

#include<stdio.h>
#define N 5
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;
}
void input(int x[], int n)
{
    int i;
    for (i = 0; i < n; ++i)
        scanf_s("%d", &x[i]);
}
void output(int x[], int n)
{
    int i;
    for (i = 0; i < n; ++i)
        printf("%d ", x[i]);
    printf("\n");
}
double average(int x[], int n)
{
    int i;
    double sum = 0;
    for (i = 0; i < n; i++)
        sum = sum + x[i];
    return sum / n;
}
void bubble_sort(int x[], int n)
{
    int i, j, t;
    for (i = 0; i < n - 1; i++)
        for (j = 0; j < n - i - 1; j++)
        {
            if (x[j] < x[j + 1])
            {
                t = x[j];
                x[j] = x[j + 1];
                x[j + 1] = t;
            }
        }
}

#include<stdio.h>
#define N 100
void dec2n(int x, int n);
int main()
{
    int x;
    printf("输入一个十进制整数：");
        while (scanf_s("%d", &x) != EOF)
        {
            dec2n(x, 2);
            dec2n(x, 8);
            dec2n(x, 16);
            printf("\n输入一个十进制整数：");
        }
        return 0;
}
void dec2n(int x, int n)
{
    int i, num = 0;
    char a[16] = { '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F' };
    char b[100];
        for (i = 0; x != 0; i++)
        {
            b[i] = a[x % n];
            x = x / n;
            num++;
        }
    for (i = num - 1; i >= 0; i--)
        printf("%c", b[i]);
    printf("\n");

}

#include<stdio.h>
#define N 100
void func(int x[][N], int n);
void output(int x[][N], int n);
int main()
{
    int x[N][N];
    int  n;
    printf("Enter n:");
    while (scanf_s("%d", &n)!= EOF)
    {
        func(x, n);
        output(x, n);
        printf("\nEnter n:");
    }
    return 0;
}
void output(int x[][N], int n)
{
    int i, j;
    for (i = 0; i < n; ++i)
    {
        for (j = 0; j < n; ++j)
            printf("%5d", x[i][j]);
        printf("\n");
    }
}
void func(int x[][N], int n)
{
    int i, j;
    for(i=0;i<n;i++)
        for (j = i; j < n; j++)
        {
            x[i][j] = i + 1;
            x[j][i] = i + 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_s(t, views1);
    strcpy_s(views1, views2);
    strcpy_s(views2, t);
    printf("交换后:\n");
    printf("views1:%s\n", views1);
    printf("views2:%s\n", views2);
    return 0;
}

#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_s(t, views[0]);
    strcpy_s(views[0], views[1]);
    strcpy_s(views[1], t);
    printf("交换后: \n");
    printf("views1: %s\n", views[0]);
    printf("views2: %s\n", views[1]);
    return 0;
}

strcpy中需要读取地址

printf在输出字符串时要读取地址

#include <stdio.h>
#include <string.h>
#define N 5
#define M 20
void bubble_sort(char str[][M], int n);
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;
}
void bubble_sort(char str[][M], int n)
{
    int i, j;
    char t[M];
    for(i=0;i<n-1;i++)
        for (j = 0; j < n - i - 1; j++)
        {
            if (strcmp(str[j], str[j + 1]) > 0)
            {
                strcpy_s(t, str[j]);
                strcpy_s(str[j], str[j + 1]);
                strcpy_s(str[j+ 1], t);
            }
        }
}