实验4 数组

TASK 1

①是，2

②不是，1

③是，是

//task1.1// 
#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:%c\n",&b[i],b[i]);
        
    printf("\n");
    
    printf("a=%p\n",a);
    printf("b=%p\n",b);
    
    return 0;
}

 

 

①不是，4

②不是，1

//task1.2 
#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;
}

 

 

TASK 2

//task 2
#include<stdio.h>
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 sum,m;
    int i;
    int a[13];
    
    if(year%400==0||year%4==0&&year%100!=0)
        a[2]=29;
    else
        a[2]=28;
    
    a[1]=a[3]=a[5]=a[7]=a[8]=a[10]=a[12]=31;
    a[4]=a[6]=a[9]=a[11]=30;
    
    for(i=1;i<month;i++)
    {
        sum+=a[i];
    }
    
    sum+=day;
    
    return sum;
}

 

 

TASK 3

//task3
#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)
{
    int i;
    double sum;
    
    for(i=0;i<n;++i)
    {
        sum+=x[i];
    }
    
    return sum/n;
}

void sort(int x[],int n)
{
    int max;
    int i,j,k;
    
    for(i=0;i<n;i++)
    {
        for(j=0;j<n-i;j++)
        {
            if(x[j]<x[j+1])
            {
                k=x[j];
                x[j]=x[j+1];
                x[j+1]=k;
            }
        }
        
    }
    
}

 

 

TASK 4

//task 4
#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)
{
    if(n==2)
    {
        int a[8];
        int i=0,j;
        
        do
        {
            a[i]=x%2;
            x/=2;
            ++i;
            
        }while(x!=0);
        
        for(j=i-1;j>=0;j--)printf("%d",a[j]);
        printf("\n");
    }
    
    else if(n==8)
    {
        int a[8];
        int i,j;
        
        do
        {
            a[i]=x%8;
            x/=8;
            ++i;
            
        }while(x!=0);
        
        for(j=i-1;j>=0;j--)printf("%d",a[j]);
        printf("\n");
    }
    
    else if(n==16)
    {
        char a[8];
        int i,j;
        
        do
        {
            
            a[i]=x%16;
            x/=16;
            i++;
            
        }while(x!=0);
        
        for(j=i-1;j>=0;j--) 
            {
                switch(a[j])
                {
                    case 10:printf("A");break;
                    case 11:printf("B");break;
                    case 12:printf("C");break;
                    case 13:printf("D");break;
                    case 14:printf("E");break;
                    case 15:printf("F");break;
                    
                    default:printf("%d",a[j]);
                }
            }
    }
}

 

 

 

 

 

TASK 5

//task 5
#include<stdio.h>

int main()
{
    int n;
    int i,j;
    
    
    printf("Enter n: ");
    while(scanf("%d",&n)!=EOF)
    {
    int a[n][n];
        for(i=0;i<n;i++)
        {
            for(j=i;j<n;j++)
                a[i][j]=i+1;
        } 
        
        for(j=0;j<n;j++)
        {
            for(i=j;i<n;i++)
                a[i][j]=j+1;
        }
        
        for(i=0;i<n;i++)
        {
            for(j=0;j<n;j++)
                printf("%2d",a[i][j]);
        
            printf("\n");
        }
        
        printf("\nEnter n: ");
    }
    
    return 0;    
} 

 

 

TASK 6

//task 6
#include<stdio.h>
#include<string.h>
#define N 80

int main()
{
    char temp[N];
    char views1[N]="hey,c,i hate u.";
    char views2[N]="hey,c,i love u.";
    
    printf("Original views:\n");
    printf("views1: %s\n",views1);
    printf("views2: %s\n",views2);
    
    
    printf("\nSwapping...\n");
    printf("\n");
    
    strcpy(temp,views1);
    strcpy(views1,views2);
    strcpy(views2,temp);
    
    printf("views1: %s\n",views1);
    printf("views2: %s\n",views2);
    
    return 0;
} 

 

 

TASK 7

//task 7 
#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 temp[M];
    
    for(i=0;i<n;i++)
    {
        for(j=0;j<n-1-i;j++)
        {
            if(strcmp(str[j],str[j+1])>0)
            {
                strcpy(temp,str[j]);
                strcpy(str[j],str[j+1]);
                strcpy(str[j+1],temp);
            }
        }
    }
    
}