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/* Note:Your choice is C IDE */#include<stdio.h>#include<string.h>#include<stdlib.h>/********定义学生结构体********/struct StuInf /*学生信息*/{int number;char name[10];char sex[4];float Chinese;float English;float Match;};struct StuLink /*学生信息链节点*/{int number;char name[10];char sex[4];float Chinese;float English;float Match;float average;struct StuLink *next;};int sizestudent=sizeof(struct StuInf);/**************录入某科目成绩*********************/float InputResult(char *lx,float d1,float d2){float result;printf("请输入%s成绩:",lx);scanf("%f",&result);while(result>d2||result<d1){printf("成绩在%6.2f--%6.2f之间，请重新输入：",d1,d2);scanf("%f",&result);}return (result);}/**************录入文字*********************/void InputWord(char *lx,char *p){char word[20];printf("请输入%s:",lx);scanf("%s",word);strcpy(p,word);}/************检测学号是否存在，若存在返回1*********/int exist(int n,FILE *fp){ struct StuInf *p;int cz=0;p=(struct StuInf*)malloc(sizestudent); /*申请一个新节点，用于读文件内容*/ rewind(fp);while(!feof(fp)){fread(p,sizestudent,1,fp); /*读出文件内容*/if(p->number==n){cz=1;break;}}return cz;}/**************计算文件长度*********************/int FileLenth(FILE *fp){long flen;fseek(fp,0L,2); /*到文件末尾*/flen=ftell(fp); /*取位置*/rewind(fp); /*回到文件头*/return flen;}/**************创建学生数据表*********************/void CreatStudent(){long start,filelen;float average;FILE *fp;struct StuInf *s;int amount=0;//记录学生个数if((fp=fopen("student","a+"))==NULL) fp=fopen("student","w+");start=FileLenth(fp);s=(struct StuInf*)malloc(sizestudent);; /*申请一个结构体空间*/while(1){ printf("请输入学号(输入0退回上一步):");scanf("%d",&s->number);if(s->number==0) /*退出*/{if (amount==0) break; /*无录入数据直接退出*/filelen=FileLenth(fp);fseek(fp,start,0);printf("|学号\t|姓名\t|性别\t| 语文| 英语| 数学| 均分|\n");while(ftell(fp)<filelen) /*将新录入的内容打印出来*/{fread(s,sizestudent,1,fp); /*读出文件内容*/average=(s->Chinese+s->English+s->Match)/3;printf("|%d\t|%s\t|%s\t|%6.2f|%6.2f|%6.2f|%6.2f|\n",s->number,s->name,s->sex,s->Chinese,s->En glish,s->Match,average);}break;}if(s->number<0){printf("\n学号不能为小于零!\n");continue;}if(exist(s->number,fp)==1) /*检测学号是否存在*/{printf("输入学号已存在!\n");continue;}InputWord("姓名",s->name); /*录入数据*/InputWord("性别",s->sex); /*录入数据*/s->Chinese=InputResult("语文",0,100); /*录入数据*/s->English=InputResult("英语",0,100); /*录入数据*/s->Match=InputResult("数学",0,100); /*录入数据*/printf("|%d\t|%s\t|%s\t|%f\t|%f\t|%f\t|\n",s->number,s->name,s->sex,s->Chinese,s->English,s->Ma tch);fwrite(s,sizestudent,1,fp); /*把数据写进文件*/amount++;}fclose(fp);}/**************查找学生数据*********************/void FindStudent(){int num;FILE *fp;struct StuInf *s;if((fp=fopen("student","r+"))==NULL) {printf("无数据可查\n");return;}s=(struct StuInf*)malloc(sizestudent); /*申请一个结构体空间*/while(1){ printf("请输入学号(输入0返回):");scanf("%d",&num);if(num==0) break; /*退出*/if(exist(num,fp)==1) /*检测学号是否存在*/{ fseek(fp,-1L*sizestudent,1); /*回滚一个记录*/fread(s,sizestudent,1,fp); /*读出文件内容*/printf("|%d\t|%s\t|%s\t|%f\t|%f\t|%f\t|\n",s->number,s->name,s->sex,s->Chinese,s->English,s->Ma tch);}elseprintf("无此学生数据\n");}fclose(fp);}/**************修改学生数据*********************/void ChangeStudent(){int num;FILE *fp;struct StuInf *s;if((fp=fopen("student","r+"))==NULL) {printf("无数据可修改\n");return;}s=(struct StuInf*)malloc(sizestudent); /*申请一个结构体空间*/while(1){ printf("请输入学号(输入0返回):");scanf("%d",&num);if(num==0) break; /*退出*/if(exist(num,fp)==1) /*检测学号是否存在*/{ fseek(fp,-1L*sizestudent,1); /*回滚一个记录*/fread(s,sizestudent,1,fp); /*读出文件内容*/printf("修改前数据\n");printf("|%d\t|%s\t|%s\t|%f\t|%f\t|%f\t|\n",s->number,s->name,s->sex,s->Chinese,s->English,s->Ma tch);InputWord("姓名",s->name);InputWord("性别m/w",s->sex);s->Chinese=InputResult("语文",0,100);s->English=InputResult("英语",0,100);s->Match=InputResult("数学",0,100);fseek(fp,-1L*sizestudent,1); /*回滚一个记录*/fwrite(s,sizestudent,1,fp); /*写新文件内容*/fseek(fp,-1L*sizestudent,1); /*回滚一个记录*/fread(s,sizestudent,1,fp); /*读出文件内容*/printf("修改后数据\n");printf("|%d\t|%s\t|%s\t|%f\t|%f\t|%f\t|\n",s->number,s->name,s->sex,s->Chinese,s->English,s->Ma tch);}elseprintf("无此学生数据\n");}fclose(fp);}/**************删除学生数据*********************/void DeleteStudent(){int num,yn;FILE *fp;struct StuInf *s;if((fp=fopen("student","r+"))==NULL) {printf("无数据可删除\n");return;}s=(struct StuInf*)malloc(sizestudent); /*申请一个结构体空间*/while(1){ printf("请输入要删除的学号(输入0返回):");scanf("%d",&num);if(num==0) break; /*退出*/if(exist(num,fp)==1) /*检测学号是否存在*/{ printf("学生数据非常重要，您确认要删除吗？（1 确认其他退回）");scanf("%d",&yn);if(yn!=1) break;printf("再确认一次（1 确认其他退回）");scanf("%d",&yn);if(yn!=1) break;s->number=0;fseek(fp,-1L*sizestudent,1); /*回滚到原记录*/fwrite(s,sizestudent,1,fp); /*清掉学号，写回*/}elseprintf("无此学生数据\n");}fclose(fp);}/************************拷贝数据到链节点*******************************************/void copytoL(struct StuLink *to,struct StuInf *s){to->number=s->number;strcpy(to->name,s->name);strcpy(to->sex,s->sex);to->Chinese=s->Chinese;to->English=s->English;to->Match=s->Match;}/************************拷贝数据到学生结点*******************************************/void copytoInf(struct StuInf *to,struct StuLink *s){to->number=s->number;strcpy(to->name,s->name);strcpy(to->sex,s->sex);to->Chinese=s->Chinese;to->English=s->English;to->Match=s->Match;}/************************排序学生表*******************************************/ /*算法思想：1、把数据拷贝到一个链表中，在接入链表的时候，每次从链表头开始查找，直到找到合适的位置，然后插入链表，这样就完成了排序。