1.task1_1
// 将图书信息写入文本文件data1.txt #include <stdio.h> #define N 7 #define M 80 typedef struct { char name[M]; // 书名 char author[M]; // 作者 } Book; int main() { Book x[N] = { {"《雕塑家》", "斯科特.麦克劳德"}, {"《灯塔》", "克里斯多夫.夏布特"}, {"《五号屠宰场》", "库尔特.冯内古特"}, {"《出卖月亮的人》", "罗伯特.海因莱茵"}, {"《大地之上》", "罗欣顿·米斯特里"}, {"《上学记》", "何兆武"}, {"《命运》", "蔡崇达"} }; int i; FILE *fp; // 以写的方式打开文本文件data1.txt fp = fopen("data1.txt", "w"); // 如果打开文件失败,输出提示信息并返回 if(fp == NULL) { printf("fail to open file\n"); return 1; } // 将结构体数组x中的图书信息写到fp指向的文件data1.txt // 同时也输出到屏幕上 for(i = 0; i < N; ++i){ fprintf(fp, "%-20s %-20s\n", x[i].name, x[i].author); printf("%-20s %-20s\n", x[i].name, x[i].author); } fclose(fp); return 0; }
task1_2
// 从文本文件data1.txt中读取图书信息,并打印输出到屏幕 #include <stdio.h> #define N 10 #define M 80 typedef struct { char name[M]; // 书名 char author[M]; // 作者 } Book; int main() { Book x[N]; int i, n; FILE *fp; // 以读的方式打开文本文件data1.txt fp = fopen("data1.txt", "r"); // 如果打开文件失败,输出提示信息并返回 if(fp == NULL) { printf("fail to open file\n"); return 1; } // 从文件中读取图书信息,保存到结构体数组x中 i = 0; while(!feof(fp)) { fscanf(fp, "%s%s", x[i].name, x[i].author); ++i; } n = i - 1; // 将图书信息打印输出到屏幕上 for(i = 0; i < n; ++i) printf("%d. %-20s%-20s\n", i+1, x[i].name, x[i].author); fclose(fp); return 0; }
change:
原因:计数错误
2.task2_1:
// 将图书信息写入二进制文件data2.dat #include <stdio.h> #define N 7 #define M 80 typedef struct { char name[M]; // 书名 char author[M]; // 作者 } Book; int main() { Book x[N] = { {"《雕塑家》", "斯科特.麦克劳德"}, {"《灯塔》", "克里斯多夫.夏布特"}, {"《五号屠宰场》", "库尔特.冯内古特"}, {"《出卖月亮的人》", "罗伯特.海因莱茵"}, {"《大地之上》", "罗欣顿·米斯特里"}, {"《上学记》", "何兆武"}, {"《命运》", "蔡崇达"} }; int i; FILE *fp; // 以写的方式打开二进制文件data2.dat fp = fopen("data2.dat", "wb"); // 如果打开文件失败,输出提示信息并返回 if(fp == NULL) { printf("fail to open file\n"); return 1; } // 将结构体数组x中的图书信息以数据块方式写入文件data2.dat fwrite(x, sizeof(Book), N, fp); fclose(fp); return 0; }
task2_2:
// 从二进制文件data2.dat读取图书信息,并打印输出到屏幕 #include <stdio.h> #define N 7 #define M 80 typedef struct { char name[M]; // 书名 char author[M]; // 作者 } Book; int main() { Book x[N]; int i; FILE *fp; // 以读的方式打开二进制文件data2.dat fp = fopen("data2.dat", "rb"); // 如果打开文件失败,输出提示信息并返回 if(fp == NULL) { printf("fail to open file\n"); return 1; } // 从文件data2.dat以数据块方式读入图书信息数据到结构体数组x fread(x, sizeof(Book), N, fp); // 在屏幕上输出结构体数组x中存储的图书信息 for(i = 0; i < N; ++i) printf("%d. %-20s%-20s\n", i+1, x[i].name, x[i].author); fclose(fp); return 0; }
3.task3_1:
// 使用fputs()将字符串写入文本文件 #include <stdio.h> #define N 5 #define M 80 int main() { char songs[N][M] = { "Working\'s Blues", "Everything Will Flow", "Streets of London", "Perfect Day", "Philadelphia"}; int i; FILE *fp; fp = fopen("data3.txt", "w"); if(fp == NULL) { printf("fail to open file\n"); return 1; } for(i = 0; i < N; ++i) { fputs(songs[i], fp); fputs("\n", fp); } fclose(fp); return 0; }
task3_2:
// 使用fgets()从文件中读取字符串并在屏幕上显示 #include <stdio.h> #define N 5 #define M 80 int main() { char songs[N][M]; int i; FILE *fp; fp = fopen("data3.txt", "r"); if(fp == NULL) { printf("fail to open file\n"); return 1; } for(i = 0; i < N; ++i) fgets(songs[i], 80, fp); for(i = 0; i < N; ++i) printf("%d. %s", i+1, songs[i]); fclose(fp); return 0; }
task3_3:
#include <stdio.h> int main() { char ch; FILE *fp; fp = fopen("data3.txt", "r"); if(fp == NULL) { printf("fail to open file\n"); return 1; } ch = fgetc(fp); while(ch != EOF) { putchar(ch); ch = fgetc(fp); } fclose(fp); return 0; }
4.task4:
#include<stdio.h> int main(){ FILE *fp; char ch; int num=0; fp=fopen("data4.txt","r"); if(fp==NULL){ printf("fail to open file\n"); return 1; } ch=fgetc(fp); while(ch!=EOF){ if(ch!=13&&ch!=32&&ch!=9){ num++; } ch=fgetc(fp); } fclose(fp); printf("%d",num-1); return 0; }
5.task5:
#include <stdio.h> #include <string.h> #include <stdlib.h> #define N 10 typedef struct { long int id; char name[20]; float objective; // 客观题得分 float subjective; // 操作题得分 float sum; char level[10]; } STU; // 函数声明 void input(STU s[], int n); void output(STU s[], int n); void process(STU s[], int n); int main() { STU stu[N]; printf("从文件读入%d个考生信息: 准考证号,姓名,客观题得分(<=40),操作题得分(<=60)\n", N); input(stu, N); printf("\n对考生信息进行处理: 计算总分,确定等级\n"); process(stu, N); printf("\n打印考生完整信息, 并保存到文件中"); output(stu, N); return 0; } // 从文本文件examinee.txt读入考生信息:准考证号,姓名,客观题得分,操作题得分 void input(STU s[], int n) { int i; FILE *fin; fin = fopen("examinee.txt", "r"); if (fin == NULL) { printf("fail to open file\n"); exit(0); } while (!feof(fin)) { for (i = 0; i < n; i++) fscanf(fin, "%ld %s %f %f", &s[i].id, s[i].name, &s[i].objective, &s[i].subjective); } fclose(fin); } // 输出考生完整信息: 准考证号,姓名,客观题得分,操作题得分,总分,等级 // 不仅输出到屏幕上,还写到文本文件result.txt中 void output(STU s[], int n) { FILE *fout; int i; // 输出到屏幕 printf("\n"); printf("准考证号\t姓名\t客观题得分\t操作题得分\t总分\t\t等级\n"); for (i = 0; i < n; i++) printf("%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", s[i].id, s[i].name, s[i].objective, s[i].subjective, s[i].sum, s[i].level); // 保存到文件 fout = fopen("result.txt", "w"); if (!fout) { printf("fail to open or create result.txt\n"); exit(0); } fprintf(fout, "准考证号\t\t姓名\t客观题得分\t操作题得分\t总分\t\t等级\n"); for (i = 0; i < n; i++) fprintf(fout, "%ld\t\t%s\t%.2f\t\t%.2f\t\t%.2f\t\t%s\n", s[i].id, s[i].name, s[i].objective, s[i].subjective, s[i].sum, s[i].level); fclose(fout); } // 对考生信息进行处理:计算总分,排序,确定等级 void process(STU s[], int n) { int i; int j; STU t; for(i=0;i<n;i++){ s[i].sum=s[i].objective+s[i].subjective; } for(i=0;i<n-1;i++){ for(j=0;j<n-1-i;j++){ if(s[j].sum<s[j+1].sum){ t=s[j]; s[j]=s[j+1]; s[j+1]=t; } } } for(i=0;i<n;i++){ if(i<n*0.1){ strcpy(s[i].level,"优秀"); }else if(i>=n*0.1&&i<=n*0.4){ strcpy(s[i].level,"合格"); }else{ strcpy(s[i].level,"不合格"); } } }
6.task6:
#include<stdio.h> #include<stdlib.h> #include<string.h> #include<time.h> #define N 80 typedef struct{ long int num; char name[80]; char cl[100]; }STU; int main(){ int i,j; long int n[5]; FILE *fp1; STU s[N]; fp1=fopen("list.txt","r"); if(fp1==NULL){ printf("fail to open file\n"); return 1; } while(!feof(fp1)) { for (i = 0; i < 80; i++) fscanf(fp1, "%ld%s%s", &s[i].num,s[i].name, s[i].cl); } fclose(fp1); FILE *fp2; fp2=fopen("lucky.txt","w"); if(fp2==NULL){ printf("fail to open file\n"); return 1; } srand(time(NULL)); for(i=0;i<5;i++){ n[i]=204942000+rand()%80+1; } for(i=0;i<5;i++){ for(j=0;j<N;j++){ if(n[i]==s[j].num){ fprintf(fp2,"%ld\t%s\t%s\n",s[j].num,s[j].name,s[j].cl); printf("%ld\t%s\t%s\n",s[j].num,s[j].name,s[j].cl); } } } fclose(fp2); return 0; }
标签:fp,return,int,char,实验,printf,include From: https://www.cnblogs.com/-piano-/p/17001544.html