实验四

#include <stdio.h>
#define N 4

int main()
{
    int a[N]={2,0,2,2};
    char b[N]={'2','0','2','2'};
    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: %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.int型数组a，在内存单元中连续存放，每个元素占用4个内存字节单元。

2.char型数组b，在内存单元中连续存放，每个元素占用1个内存字节单元。

3.数组名a对应的值和&a[0]一样,数组名b对应的值和&b[0]一样.

#include<stdio.h>
#define N 2
#define M 3

int main()
{
    int a[N][M] = {{1,2,3},{4,5,6}};
    char b[N][M] = {{'1','2','3'},{'4','5','6'}};
    int i,j;
    
    printf("sizeof(int) = %d\n",sizeof(int));
    printf("sizeof(char) = %d\n",sizeof(char));
    printf("\n");
    
    //输出二维数组中每个元素的地址、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");
    
    //输出二维数组中每个元素的地址、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; 
    
    
}

 

 

 1、int型二维数组a，在内存中是“按行连续存放”的，每个元素占用4个内存字节单元；

2、char型二维数组b，在内存中是“按行连续存放”的，每个元素占用1个内存字节单元；

#include <stdio.h>
#define N 2
#define M 3
int main()
{
    int a[N][M] = {{1, 2, 3}, {4, 5, 6}};
    char b[N][M] = {{'1', '2', '3'}, {'4', '5', '6'}};
    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;
}

 

 

1.按行连续存放，每个元素占用4个内存字节单元

2.按行连续存放，每个元素占用1个内存字节单元

#include<stdio.h>
int days_of_year(int year,int month,int day);//函数声明
int main()
{
int year,month,day;
int days;
while(scanf("%d%d%d",&year,&month,&day)!=EOF)//按下Ctrl+Z终止
{
days=days_of_year(year,month,day);//函数调用
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 sum=0,i,a[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
if(year % 400 == 0 || year % 100 != 0 && year % 4 == 0)
 {a[2]++;}
for(i=1;i<month;i++)
{
sum+=a[i];
}
sum+=day;
return sum;
}
//函数定义
//补足函数days_of_year的定义
//xxx

 

 

#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 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);
    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("%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)
{
    double s=0;
    int i;
    for(i=0;i<n;i++)
        s+=x[i];
        
    return (s/n);    
}
void sort(int x[],int n)
{
    int i,j,t;
    for(j=0;j<n-1;j++)
    {
        for(i=0;i<n-1-j;i++)
        {
            if(x[i]>x[i+1])
            {
                t=x[i];
                x[i]=x[i+1];
                x[i+1]=t;
            }
        }
            
    }
    for(i=0;i<=n/2;i++)
        {
            t=x[i];
            x[i]=x[n-i-1];
            x[n-i-1]=t;
        }
}

 

 

#include<stdio.h>
void dec2n(int x, int n);

int main()
{
    int x;
    
    printf("输入一个十进制整数: ");
    scanf("%d", &x);
    
    dec2n(x, 2); 
    dec2n(x, 8); 
    dec2n(x, 16); 
    
    return 0;
}

void dec2n(int x, int n)
{
    int a[80];
    int  i=1,k,j=0;
    
    while(x!=0)
    {
        i=x%n;
        a[j++]=i;
        x=x/n;
    }
    
    for(k=j-1;k>=0;k--)
    {
        if(a[k]>9&&a[k]<16)
            printf("%c",a[k]-10+'A');
        else
            printf("%d",a[k]);
    }
    
    printf("\n");
        
}

 

 

#include<stdio.h>

int main()

{
     int i,j,k,n;
    printf("Enter n:");
    while(scanf("%d",&n)!= EOF)
    {
        for(i=1;i<=n;i++)
        {
           for(j=1;j<=n;j++)
            {
               k=i>j?j:i;
               printf("%3d",k);
            }
            printf("\n");
        }
    }
    return 0;
}

 

 

#include<stdio.h>
#define N 80
 
int main()
{
    char views1[N] = "hey,c,i hate u.";
    char views2[N] = "hey,c,i,love u.";
    int i;
  
 
    printf("original views:\n");
    printf("views1:%s\n", views1);
    printf("views2:%s\n", views2);
 
    printf("\n");
 
    for (i = 0; i < N; i++)
    {
        views1[20] = views1[i];
        views1[i] = views2[i];
        views2[i] = views1[20];
    }
 
    printf("swapping...\n");
 
    printf("views1:%s\n", views1);
    printf("views2:%s\n", views2);
 
    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;
      char a[M];
    for(i=0;i<N;i++)
    {
        for(j=0;j<N-1;j++)
        { 
            if(strcmp(str[j],str[j+1])>0)
               {
                strcpy(a,str[j]);
                   strcpy(str[j],str[j+1]);
                   strcpy(str[j+1],a);
        
            }
    
          }
    }
    

}