实验4

task1-1

#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、是；4个字节

2、是；1个字节

3、是；是

task1-2

#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;

　　

1、是；4个内存字节

2、是；1个内存字节

task2

#include<stdio.h>
#include<stdlib.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);
	
	}
	system("pause");
return 0;
}
int days_of_year(int year,int month,int day)
{
int flag=0,ans=0;
if((year%400==0)||(year%4==0&&year%100!=0))
{flag=1;}
ans+=day;
switch(month)
{
case 12:
	ans+=30;
case 11:
	ans+=31;
case 10:
	ans+=30;
case 9:
	ans+=31;
case 8:
	ans+=30;
case 7:
	ans+=30;
case 6:
	ans+=31;
case 5:
	ans+=30;
case 4:
	ans+=31;
case 3:
	if(flag==0)
	{
		ans+=29;
	}
	else
	{
		ans+=28;
	}
case 2:
	ans+=31;
case 1:
	ans+=0;
		
}

	return ans;
}

　　

task3

#include <stdio.h>
#include<stdlib.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);
	system("pause");
    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,s=0;
	double aver;
	for(i=0;i<n;++i)
	{s=s+x[i];}
	aver=(double)s/N;
	return aver;
}
void bubble_sort(int x[], int n){
  int i,t;
  int flag=0;
  while(flag==0){
  for(i=0;i<n;++i)
  {flag=1;
 if(x[i]<x[i+1])
 {flag=0;
 t=x[i];
  x[i]=x[i+1];
  x[i+1]=t;
 }
  }
  }
  return;
}

　　

task 4

#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 t,i,j;
    char arr[N] = { '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F' };
    char list[N];
    for (i = 0; x > 0; i++)
    {
        t = x % n;
        list[i] = arr[t];
        x /= n;
    }
    for (j = i - 1; j >= 0; j--)
    {
        printf("%c", list[j]);
    }
    printf("\n");
    return;
}

　　

 

task 5

#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 (j >= i) x[i][j] = i + 1;
            else x[i][j] = j + 1;
        }
    }
    return;
}

　　

 

task 6

#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(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;
}

　　

task 6_2

#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;
}

　　

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, k, flag = 1;
    char t[100];
    while (flag == 1)
    {
        flag = 0;
        for (i = 0; i < n - 1; i++)
        {
            if (strcmp(str[i], str[i + 1]) > 0)
            {
                strcpy_s(t, str[i]);
                strcpy_s(str[i], str[i + 1]);
                strcpy_s(str[i + 1], t);
                flag = 1;
            }
        }
    }

    return;
}