实验四

int是连续存放，四个字节
char也是连续存放，一个字节
一样
一样


#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;
}

int是连续存放，四个字节
char是连续存放，一个字节



#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("%p: %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;
}

#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\n", year, month, day, days);
    }
    return 0;
}
int days_of_year(int year, int month, int day) {
    int n[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };
    int x,r=0;
    if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
        n[2] = 29;
    for (x = 1; x < month; x++)
        r += n[x];
    r = r + day;
    return r;

}

#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 s=0.0;
    for (i = 0; i < n; i++)
        s += x[i];
    s = s / n;
    return s;
}

void bubble_sort(int x[], int n) {
    int i, j,t,r;

    for(i=0;i<n;i++)
        for(j=i+1;j<n;j++)
            if (x[j] > x[i])
            {
                t = x[i];
                x[i] = x[j];
                x[j] = t;
            }
    for (r = 0; r < n; r++)
        printf("%d\t", x[r]);
    printf("\n");
}

#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_s("%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 r[16] = { '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F' };
    int a,i=0;
    char b[100]={'0'};
    while (x != 0)
    {
        a = x % n;
        x /= n;
        b[i++] = r[a];
    }
    for (; 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 i, j, 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 = 0; j <= n; j++)
        {
            if (i <= j)
                x[i][j] = i + 1;
            else
                x[i][j] = j+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);
    
    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]);
    
    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;
}

#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); 
    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, a = 0,b;
    char s[M];
    
        for (i = N - 2; i >= 0; i--)
            for (j = 0; j < M - 1; j++)
            {
                if (str[i][j] < str[i + 1][j])
                    break;
                if (str[i][j] > str[i + 1][j])
                {
                    strcpy_s(s, str[i]);
                    strcpy_s(str[i], str[i + 1]);
                    strcpy_s(str[i + 1], s);
                    break;
                }
            }
}