红皮书 - C语言程序设计实用教程参考答案(9)

int main(){ FILE *p;

char str[]=\ int i=0,length;

length = strlen(str);

p=fopen(\ for(i=0;i

#include int main(){ FILE *p; char ch;

p=fopen(\ if(p!=NULL){ ch=fgetc(p); while(ch!=EOF){ printf(\ ch=fgetc(p); } fclose(p); } else{ printf(\文件不存在\ }

getchar(); return 0; } 13

#include

int main(){

double x=1.2,y=3.4;

int size=sizeof(double); FILE *p; int m=0;

p=fopen(\ m=fwrite(&x,size,1,p);

if(m==1){

printf(\成功将数据%lf写入二进制文件.\\n\

}

m=fwrite(&y,size,1,p);

if(m==1){

printf(\成功将数据%lf写入二进制文件.\\n\ } 12．

#include int main(){ FILE *p; double x,y; int m;

int size=sizeof(double);

p=fopen(\ m=fread(&x,size,1,p); if(m==1){ printf(\读入的一个double型数据存放在x中:\\n\ printf(\ }

m=fread(&y,size,1,p); if(m==1){ printf(\读入的一个double型数据存放在y中:\\n\ printf(\ }

fclose(p); return 0; } 13．

#include

#define N 3 //学生数量是3 typedef struct {

char name[20]; float math; float eng; float chi; float aver; } GOODS;

void saveGoods(GOODS [],char *);

} return 0;

fclose(p);

void outputGoods(char *); int main(){ int i;

GOODS goods[N];

char fileName[]=\ for(i=0;i

printf(\输入第%d个学生的语文分数:\ scanf(\ getchar();//消耗回车

goods[i].aver=(goods[i].math+goods[i].eng+goods[i].chi)/3; }

saveGoods(goods,fileName);

printf(\文件%s中保存的学生信息:\\n\ outputGoods(fileName); return 0; }

void saveGoods(GOODS goods[],char *fileName){ FILE *p; int i;

p=fopen(fileName,\ for(i=0;i

fclose(p); }

void outputGoods(char * fileName){ FILE *p; int i;

GOODS goods[N];

p=fopen(fileName,\ for(i=0;i

for(i=0;i

goods[i].name,goods[i].math,goods[i].eng,goods[i].chi,goods[i].aver); }

fclose(p); } 16．

#include

#define N 3 //学生数量是3 typedef struct {

char name[20]; float math; float eng; float chi; float aver; } GOODS;

void outputGoods(char *); int main(){

char fileName[]=\

printf(\文件%s中保存的学生信息:\\n\ outputGoods(fileName); return 0; }

void outputGoods(char * fileName){ FILE *p; int i;

GOODS goods[N];

p=fopen(fileName,\ for(i=0;i

for(i=0;i

fclose(p); }

17． 请预先在c:\\\\1000\\\\中准备两个文本文件ok1.txt和ok2.txt。

#include int main(){ FILE *p1,*p2; char ch;

//long position =0;

printf(\开始合并文件\\n\

p1=fopen(\ p2=fopen(\ ch=fgetc(p2);

while(!feof(p2)){ fputc(ch,p1); ch=fgetc(p2); }

fclose(p2);

rewind(p1); //将读写位置定位到文件的开头 printf(\读取到合并后的文件:\\n\ ch=fgetc(p1);

while(ch != EOF){ printf(\ ch=fgetc(p1); }

fclose(p1);

getchar(); return 0; }

18．请预先在c:\\\\1000\\\\中准备两个文本文件ok1.txt和ok2.txt。

#include int main(){

FILE *p1,*p2,*p3; char ch;

printf(\开始合并文件\\n\

p1=fopen(\ p2=fopen(\ p3=fopen(\ ch=fgetc(p1);

while(!feof(p1)){ fputc(ch,p3); ch=fgetc(p1); }

fclose(p1);

while(!feof(p2)){ fputc(ch,p3); ch=fgetc(p2); }

fclose(p2);

rewind(p3); //将读写位置定位到文件的开头