实验四

1.1 是 4 是 1
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");
// 输出一维int数组a中每个元素的地址、值
for (i = 0; i < N; ++i)
printf("%p: %d\n", &a[i], a[i]);
printf("\n");
// 输出一维char数组b中每个元素的地址、值
for (i = 0; i < N; ++i)
printf("%p: %c\n", &b[i], b[i]);
printf("\n");
// 输出数组名a和b对应的值
printf("a = %p\n", a);
printf("b = %p\n", b);
return 0;
}

是

#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;
// 输出二维数组a中每个元素的地址和值
for (i = 0; i < N; ++i)
for (j = 0; j < M; ++j)
printf("%p: %d\n", &a[i][j], a[i][j]);printf("\n");
// 输出二维数组a中每个元素的地址和值
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("%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 days=0,ans;
    int a[N]={0,31,28,31,30,31,30,31,31,30,31,30,31};
    for(int i=1;i<month;i++){
    if(year%4==0&&year%100!=0||year%400==0){
        a[2]=29;
    }
    days=days+a[i];
    
  }ans=days+day;
  return ans;
}

#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");
}
double average(int x[],int n){
    int sum=0;double ans;
    for(int i=0;i<n;i++){
        sum=sum+x[i];
    }
    ans=1.0*sum/n;
    return ans;
}
void bubble_sort(int x[], int n){
    int t;
    for(int j=0;j<n;j++){
        for(int i=0;i<n-j-1;i++){
            if(x[i]<x[i+1]){
                t=x[i];
                x[i]=x[i+1];
                x[i+1]=t;
                
            }
        }
    }

}

#include <stdio.h>
#include<string.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("%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){
    int i=0,y,j=0;int a[N];
    char H[N],h;
    if(n==16){
    if(x<16){
        if(x>=0&&x<=9)h=x+'0';
        else h=x-10+'A';
        printf("%c",h);
    }
    else{
        while(x)
        {
            y=x%16;
            x=x/16;
            if(y>=0&&y<=9)
                H[j++]=y+'0';
            else
                H[j++]=y-10+'A';
        }
        for(i=j-1; i>=0; i--)
        {
            printf("%c",H[i]);
        }
        printf("\n");
        }
}
    
else {
    while(x!=0){
        
        a[i]=x%n;
        x=x/n;
        i++;
    }
    for(int j=i-1;j>=0;j--){
        printf("%d",a[j]);
    }
    printf("\n");}
}

#include <stdio.h>
#define N 100
// 函数声明
void func(int x[][N], int n); 
void output(int x[][N], int n); // 注意：两维数组作为形参的语法
int main() {
int x[N][N];
int i, j, n;
printf("Enter n: ");
while(scanf("%d", &n) != EOF) {
func(x, n); // 注意：两维数组作为实参的语法
output(x, n); // 注意：两维数组作为实参的语法
printf("\nEnter n: ");
}
return 0;
}
// 函数定义
// 功能：输出两维数组x中的数据，数据项n行、n列
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=n-1;i>=0;i--){
        for(j=n-1;j>=0;j--){
            x[i][j]=i+1;
            x[j][i]=x[i][j];
            
        }
    }
    
}

#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;
}

#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;
}

#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;
}
void bubble_sort(char str[][M], int n){
    char b[M];
    for(int j=0;j<n;j++){
    for(int i=0;i<n-i-1;i++){
    
        if(strcmp(str[i],str[i+1])>0){
            strcpy(b,str[i]);
            strcpy(str[i],str[i+1]);
            strcpy(str[i+1],b);
        }
    }
    }
    
    
}