实验五

1.1

#include <stdio.h>

int main(int argc, char *argv[]) 
{
    int i;

    for(i = 1; i < argc; ++i)
        printf("hello, %s\n", argv[i]);

    return 0;
}

void func(int argc, char *argv[])
{
    int i,j;
    char *temp;  
    for(j = 1; j < argc; j++) 
    {
        for(i = 1; i < argc - j; i++)  
        {
            if(strcmp(argv[i], argv[i+1]) > 0)
            {
                temp = argv[i];
                argv[i] = argv[i+1];
                argv[i+1] = temp;
            }
        }
    }
}

1.查找出一组数据中的最大值和最小值
2.指向main函数中定义的min和max变量的地址

1.2

#include <stdio.h>
#define N 5

void input(int x[], int n);
void output(int x[], int n);
int *find_max(int x[], int n);

int main() 
{
    int a[N];
    int *pmax;

    printf("录入%d个数据:\n", N);
    input(a, N);

    printf("数据是: \n");
    output(a, N);

    printf("数据处理...\n");
    pmax = find_max(a, N);

    printf("输出结果:\n");
    printf("max = %d\n", *pmax);

    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");
}

int *find_max(int x[], int n) 
{
    int max_index = 0;
    int i;

    for(i = 0; i < n; ++i)
        if(x[i] > x[max_index])
            max_index = i;
    
    return &x[max_index];
}

1.返回一组数据中的最大值
2.可以。在修改后的代码中，首先ptr为&x[0] 。然后通过for循环遍历数组，当遇到比*ptr更大的元素x[i]时，更新ptr为该元素的地址&x[i] 。循环结束后，ptr指向数组中的最大值元素，最后return ptr;返回最大值元素的地址，和原函数功能一致

2.1

#include <stdio.h>
#include <string.h>
#define N 80

int main() 
{
    char s1[N] = "Learning makes me happy";
    char s2[N] = "Learning makes me sleepy";
    char tmp[N];

    printf("sizeof(s1) vs. strlen(s1): \n");
    printf("sizeof(s1) = %d\n", sizeof(s1));
    printf("strlen(s1) = %d\n", strlen(s1));

    printf("\nbefore swap: \n");
    printf("s1: %s\n", s1);
    printf("s2: %s\n", s2);

    printf("\nswapping...\n");
    strcpy(tmp, s1);
    strcpy(s1, s2);
    strcpy(s2, tmp);

    printf("\nafter swap: \n");
    printf("s1: %s\n", s1);
    printf("s2: %s\n", s2);

    return 0;
}

1.80.计算的是s1的长度.统计的是s1中的字符数
2.可以
3.交换

2.2

#include <stdio.h>
#include <string.h>
#define N 80

int main() 
{
    char *s1 = "Learning makes me happy";
    char *s2 = "Learning makes me sleepy";
    char *tmp;

    printf("sizeof(s1) vs. strlen(s1): \n");
    printf("sizeof(s1) = %d\n", sizeof(s1));
    printf("strlen(s1) = %d\n", strlen(s1));

    printf("\nbefore swap: \n");
    printf("s1: %s\n", s1);
    printf("s2: %s\n", s2);

    printf("\nswapping...\n");
    tmp = s1;
    s1 = s2;
    s2 = tmp;

    printf("\nafter swap: \n");
    printf("s1: %s\n", s1);
    printf("s2: %s\n", s2);

    return 0;
}

1.首字母的地址.计算的是数组s1在内存中占用的字节数.统计的是字符串s1中有效字符个数
2.不能,字符数组名是一个地址常量,不能对其直接进行赋值操作
3.交换

#include <stdio.h>

int main() 
{
    int x[2][4] = {{1, 9, 8, 4}, {2, 0, 4, 9}};
    int i, j;
    int *ptr1;     
    int(*ptr2)[4]; 

    printf("输出1: 使用数组名、下标直接访问二维数组元素\n");
    for (i = 0; i < 2; ++i) {
        for (j = 0; j < 4; ++j)
            printf("%d ", x[i][j]);
        printf("\n");
    }

    printf("\n输出2: 使用指针变量ptr1(指向元素)间接访问\n");
    for (ptr1 = &x[0][0], i = 0; ptr1 < &x[0][0] + 8; ++ptr1, ++i) 
    {
        printf("%d ", *ptr1);

        if ((i + 1) % 4 == 0)
            printf("\n");
    }
                         
    printf("\n输出3: 使用指针变量ptr2(指向一维数组)间接访问\n");
    for (ptr2 = x; ptr2 < x + 2; ++ptr2) 
    {
        for (j = 0; j < 4; ++j)
            printf("%d ", *(*ptr2 + j));
        printf("\n");
    }

    return 0;
}

ptr1依次指向数组中每个元素,通过*ptr1来访问当前指针所指向的二维数组元素并输出
ptr2指向数组,通过*(*ptr2 + j)来访问当前行中的各个元素并输出

#include <stdio.h>
#define N 80

void replace(char *str, char old_char, char new_char); 

int main() 
{
    char text[N] = "Programming is difficult or not, it is a question.";

    printf("原始文本: \n");
    printf("%s\n", text);

    replace(text, 'i', '*'); 

    printf("处理后文本: \n");
    printf("%s\n", text);

    return 0;
}

void replace(char *str, char old_char, char new_char) 
{
    int i;

    while(*str) 
    {
        if(*str == old_char)
            *str = new_char;
        str++;
    }
}

1.将字母i替换成*
2.可以

#include <stdio.h>
#define N 80

char *str_trunc(char *str, char x);

int main() 
{
    char str[N];
    char ch;

    while(printf("输入字符串: "), gets(str) != NULL) 
    {
        printf("输入一个字符: ");
        ch = getchar();

        printf("截断处理...\n");
        str_trunc(str, ch);      

        printf("截断处理后的字符串: %s\n\n", str);
        getchar();
    }

    return 0;
}
char *str_trunc(char *str, char x)
{
    char *p=str;
    while(*p!='\0')
    {
        if(*p==x)
        {
            *p='\0';
            break;
        }
        p++;
    }
    return str;
}

1.getchar()存放最后输入的回车符

#include <stdio.h>
#include <string.h>
#define N 5

int check_id(char *str); 

int main()
{
    char *pid[N] = {"31010120000721656X",
                    "3301061996X0203301",
                    "53010220051126571",
                    "510104199211197977",
                    "53010220051126133Y"};
    int i;

    for (i = 0; i < N; ++i)
        if (check_id(pid[i])) 
            printf("%s\tTrue\n", pid[i]);
        else
            printf("%s\tFalse\n", pid[i]);

    return 0;
}

int check_id(char *str) 
{
    int i;
    if(strlen(str)!=18)
    {
        return 0;
    }
    for(i=0;i<17;i++)
    {
        if(str[i]<'0'||str[i]>'9')
        {
            return 0;
        }    
    } 
    if(str[17]<'0'||str[17]>'9'&&str[17]!='X')
        {
            return 0;
        }
    return 1;
}

#include <stdio.h>
#define N 80
void encoder(char *str, int n); 
void decoder(char *str, int n); 

int main() 
{
    char words[N];
    int n;

    printf("输入英文文本: ");
    gets(words);

    printf("输入n: ");
    scanf("%d", &n);

    printf("编码后的英文文本: ");
    encoder(words, n);  
    printf("%s\n", words);

    printf("对编码后的英文文本解码: ");
    decoder(words, n); 
    printf("%s\n", words);

    return 0;
}

void encoder(char *str, int n) 
{
    while(*str!='\0')
    {
        if((*str>='a' && *str<='z')||(*str>='A' && *str<='Z'))
        {
            if(*str>='a' && *str<='z')
            {
                *str=((*str-'a'+n)%26)+'A';
            }
        }
        str++;
    }
}

void decoder(char *str, int n) 
{
    while(*str!='\0')
    {
        if((*str>='a' && *str<='z')||(*str>='A' && *str<='Z'))
        {
            if(*str>='a' && *str<='z')
            {
                *str=((*str-'a'+n+26)%26)+'a';
            }
            else
            {
                *str=((*str-'A'+n+26)%26)+'A';
            }
        }
        str++;
    }
}

#include <stdio.h>

int main(int argc, char *argv[]) 
{
    int i;

    for(i = 1; i < argc; ++i)
        printf("hello, %s\n", argv[i]);

    return 0;
}

#include <stdio.h>

int main(int argc, char *argv[]) 
{
    int i;

    for(i = 1; i < argc; ++i)
        printf("hello, %s\n", argv[i]);

    return 0;
}

void func(int argc, char *argv[])
{
    int i,j;
    char *temp;  
    for(j = 1; j < argc; j++) 
    {
        for(i = 1; i < argc - j; i++)  
        {
            if(strcmp(argv[i], argv[i+1]) > 0)
            {
                temp = argv[i];
                argv[i] = argv[i+1];
                argv[i+1] = temp;
            }
        }
    }
}

posted @ 2025-05-13 21:13 周丹婷阅读(81) 评论(0) 收藏举报

刷新页面返回顶部

2005-z

实验五

公告