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// 下面是前期的点餐系统的基础数据维护,其它功能你可以自己尝试写,如果遇到什么问题可以提出来追问喔，相信你可以解决的(我怕代码太多提交会受字数限制)。
// mm.h 头文件#include<stdio.h>
#include<stdlib.h>
#define MENU_NUM_MAX 100 // 假设有100种菜式
#define LEN sizeof(struct MenuInfo)
struct MenuInfo
{
int ID
char MenuName[20]
float price
}Menu[MENU_NUM_MAX]
/* 基础数据维护 */
void AddMenu()
{
FILE *fp
int menu_num
printf("\t\t 你要添加多少种菜?:")
scanf("%d",&menu_num)
for(int i=0i<menu_numi++)
{
printf("\n") // added this line
printf("\t\t请输入ID:")
scanf("%d",&Menu[i].ID)
printf("\t\t请输入菜名:")
scanf("%s",Menu[i].MenuName)
printf("\t\t请输入[%s]菜的价格:",Menu[i].MenuName)
Menu[i].price=0.0f //initial float price
scanf("%f",&Menu[i].price)
fflush(stdin)
}
if((fp=fopen("MenuInfo.dat","ab"))==NULL) // open binary file
{
printf("Can't open file\n")
exit(1)
}
for(int j=0j<menu_numj++)
{
if(fwrite(&Menu[j],LEN,1,fp)!=1) //writing data to binary file
printf("Error writing file.\n")
}
fclose(fp) // close file point
}
void DisplayMenuInfo()
{
FILE *fp
printf("\n\t\tID 菜名\t\t价格\n") // column headings
if((fp=fopen("MenuInfo.dat","rb"))==NULL) // open binary file
{
printf("Can't open file\n")
exit(1)
}
int i=0
do
{
fseek(fp,i*LEN,SEEK_SET) // move file head location
if(fread(&Menu[i],LEN,1,fp)) // read data save to structure variable
{
printf("\t\t%d %5s\t\t%5.1f元\n",Menu[i].ID,Menu[i].MenuName,Menu[i].price)
i++
}
}while(!feof(fp))
fclose(fp)
}
void DeleteToMenu()
{
FILE *fp
int MenuID
int todelete=-1
int i=0
printf("请输入要删除的菜名的ID:")
scanf("%d",&MenuID)
/* load or reload the file and check that record with that ID exists */
if((fp=fopen("MenuInfo.dat","rb"))==NULL) // open binary file
{
printf("Can't open file\n")
exit(1)
}
do
{
fseek(fp,i*LEN,SEEK_SET) // move file head location
if(fread(&Menu[i],LEN,1,fp))
{
if (Menu[i].ID==MenuID) todelete=i
i++
}
}while(!feof(fp))
fclose(fp)
if (todelete==-1)
{
printf("A menu with that ID doesn't exist\n")
}
else
{
/* write records back to file excluding one to be deleted */
if((fp=fopen("MenuInfo.dat","wb"))==NULL) // open binary file
{
printf("Can't open file\n")
exit(1)
}
for(int j=0j<ij++)
{
if (j==todelete) continue /* skip record to be deleted */
if(fwrite(&Menu[j],LEN,1,fp)!=1) //writing data to binary file
printf("Error writing file.\n")
}
fclose(fp) // close file point
}
}
void FindMenu()
{
FILE *fp
int MenuID
bool find_mark=false
printf("\n\t\t请输入你要查找的菜名ID:")
scanf("%d",&MenuID)
printf("\n\t\tID 菜名\t\t价格\n") // column headings
if((fp=fopen("MenuInfo.dat","rb"))==NULL) // open binary file
{
printf("Can't open file\n")
exit(1)
}
int i=0
do
{
fseek(fp,i*LEN,SEEK_SET) // move file head location
fread(&Menu[i],LEN,1,fp) // read data save to structure variable
if(Menu[i].ID==MenuID)
{
printf("\t\t%d %5s\t\t%5.1f元\n",Menu[i].ID,Menu[i].MenuName,Menu[i].price)
find_mark=true
break
}
i++
}while(!feof(fp))
if(!find_mark) printf("\n\t 尊敬的客户:我们餐厅没有你要点的菜喔,你可以试试我们的招牌菜啊^-^.\n")
fclose(fp)
}
/* 基础数据维护完毕 */
// sc.cpp主文件
#include <stdio.h>
#include <stdlib.h>
#include "mm.h"
void main(void)
{
//AddMenu()
//DisplayMenuInfo()
//FindMenu()
}
#include<stdio.h>#include<stdlib.h>
#define ROW1 2
#define COL1 2
#define ROW2 COL1
#define COL2 4
int main(void)
{
int arr1[ROW1][COL1]=
{
{1,2},
{3,4}
},
arr2[ROW2][COL2]=
{
{1,2,1,2},
{1,2,1,2}
},
arr3[ROW2][COL2],i,j,k
for(i=0i<ROW1i++)
{
for(j=0j<COL2j++)
{
arr3[i][j]=0
for(k=0k<ROW2k++)
{
arr3[i][j]+=arr1[i][k]*arr2[k][j]
}
}
}
for(i=0i<ROW2i++)
{
for(j=0j<COL2j++)
{
printf("%-3d",arr3[i][j])
}
printf("\n")
}
system("pause")
return(0)
}
#include <stdio.h> #include <stdlib.h> #include <errno.h> #include <string.h> #include <netdb.h> #include <sys/types.h> #include <netinet/in.h> #include <sys/socket.h> #define SERVPORT 3333 #define MAXDATASIZE 100 /*每次最大数据传输量 */ int main(int argc, char *argv[]) { int sockfd, recvbytes char buf[MAXDATASIZE] struct hostent *host struct sockaddr_in serv_addr if (argc <2) { fprintf(stderr,"Please enter the server's hostname!\")exit(1) } if ((host=gethostbyname(argv[1]))==NULL) { perror("gethostbyname出错！")exit(1)} if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("socket创建出错！")exit(1) } //初始化客户端 serv_addr.sin_family=AF_INET serv_addr.sin_port=htons(SERVPORT) serv_addr.sin_addr = *((struct in_addr *)host->h_addr) bzero(&(serv_addr.sin_zero),8) //connect if (connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(struct sockaddr)) == -1) { perror("connect error！")exit(1)} //recv if ((recvbytes=recv(sockfd, buf, MAXDATASIZE, 0)) ==-1) { perror("recv出错！")exit(1)} buf[recvbytes] = '\\0' printf("Received: %s",buf) close(sockfd) return 0 } 客户端#include <stdio.h> #include <stdlib.h> #include <errno.h> #include <string.h> #include <sys/types.h> #include <netinet/in.h> #include <sys/socket.h> #include <sys/wait.h> #define SERVPORT 3333 /*服务器监听端口号 */ #define BACKLOG 10 /* 最大同时连接请求数 */ int main() { int sockfd,client_fd,sin_size/*sock_fd：监听socket；client_fd：数据传输socket */ struct sockaddr_in my_addr/* 本机地址信息 */ struct sockaddr_in remote_addr/* 客户端地址信息 */ //创建一个套接字，PF_INET，流式， if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("socket")exit(1) } //初始化服务端 my_addr.sin_family=AF_INET my_addr.sin_port=htons(SERVPORT) my_addr.sin_addr.s_addr = INADDR_ANY bzero(&(my_addr.sin_zero),8) //将套接字地址与所创建的套接字号联系起来 if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) { perror("bind") exit(1) } //愿意接收连接 if (listen(sockfd, BACKLOG) == -1) { perror("listen") exit(1) } while(1) { sin_size = sizeof(struct sockaddr_in) if ((client_fd = accept(sockfd, (struct sockaddr *)&remote_addr, &sin_size)) == -1){ perror("accept") continue} printf("received a connection from %s\", inet_ntoa(remote_addr.sin_addr)) if (!fork()) { /* 子进程代码段 */ if (send(client_fd, "Hello, you are connected!\", 26, 0) == -1) perror("send")close(client_fd)exit(0)} close(client_fd) } return 0 } 服务端 内容自己加
