#include <stdio.h> #define N 5 #define M 80 typedef struct { char name[M]; // 书名 char author[M]; // 作者 } Book; int main() { Book x[N] = { {"一九八四", "乔治.奥威尔"}, {"美丽新世界", "赫胥黎"}, {"昨日的世界", "斯蒂芬.茨威格"}, {"万历十五年", "黄仁宇"}, {"一只特立独行的猪", "王小波"} }; int i; FILE *fp; fp = fopen("data1.txt", "w"); if (fp == NULL) { printf("fail to open file\n"); return 1; } 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; }
#include <stdio.h> #define N 5 #define M 80 typedef struct { char name[M]; char author[M]; } Book; int main() { Book x[N]; int i; FILE *fp; fp = fopen("data1.txt", "r"); if (fp == NULL) { printf("fail to open file\n"); return 1; } for (i = 0; i < N; ++i) { fscanf(fp, "%s %s\n", x[i].name, x[i].author); printf("%-20s %-20s\n", x[i].name, x[i].author); } fclose(fp); return 0; }
x[i].name和x[i].author都是字符串,他们的地址就是本身。
#include <stdio.h> #define N 5 #define M 80 typedef struct { char name[M]; char author[M]; } Book; int main() { Book x[N] = { {"一九八四", "乔治.奥威尔"}, {"美丽新世界", "赫胥黎"}, {"昨日的世界", "斯蒂芬.茨威格"}, {"万历十五年", "黄仁宇"}, {"一只特立独行的猪", "王小波"} }; int i; FILE *fp; fp = fopen("data2.dat", "wb"); if (fp == NULL) { printf("fail to open file\n"); return 1; } fwrite(x, sizeof(Book), N, fp); fclose(fp); return 0; }
#include <stdio.h> #define N 5 #define M 80 typedef struct { char name[M]; char author[M]; } Book; int main() { Book x[N]; int i; FILE *fp; fp = fopen("data2.dat", "rb"); if (fp == NULL) { printf("fail to open file\n"); return 1; } fread(x, sizeof(Book), N, fp); for (i = 0; i < N; ++i) printf("%-20s%-20s\n", x[i].name, x[i].author); fclose(fp); return 0; }
#include <stdio.h> int main() { FILE *fin, *fout; char ch; fin = fopen("data3_1.txt", "r"); if (fin == NULL) { printf("fail to open data3_1.txt\n"); return 1; } fout = fopen("data3_2.txt", "w"); if (fout == NULL) { printf("fail to open data3_2.txt\n"); return 1; } while ( !feof(fin) ) { ch = fgetc(fin); if (ch >= 'a' && ch <= 'z') ch -= 32; fputc(ch, fout); } fclose(fin); fclose(fout); return 0; }
#include <stdio.h> int main() { int i, num = 0; char ch; FILE *fin; fin = fopen("data3_1.txt", "r"); if (fin == NULL) { printf("fail to open data3_1.txt\n"); return 1; } while (!feof(fin)) { ch = fgetc(fin); if (ch != ' ' && ch != '\t' && ch != '\n' && ch != EOF) num = num + 1; } fclose(fin); printf("data3_1.txt中共包含字符数:%d个", num); return 0; }
#include <stdio.h> #define N 5 typedef struct { long no; char name[20]; int score; } STU; int findMinlist(STU s[], int n, STU t[]); int main() { STU stu[N], minlist[N]; int count, i; FILE *fin, *fout; fin = fopen("data4_1.txt", "r"); if (fin == NULL) { printf("fail to open file\n"); return 1; } for (i = 0; i < N; ++i) { fscanf(fin, "%ld %s %d", &stu[i].no, stu[i].name, &stu[i].score); printf("%ld %s %d\n", stu[i].no, stu[i].name, stu[i].score); } fclose(fin); count = findMinlist(stu, N, minlist); printf("\n一共有%d个最低分,信息如下: \n", count); for (i = 0; i < count; ++i) printf("%ld %s %d\n", minlist[i].no, minlist[i].name, minlist[i].score); fout = fopen("data4_2.txt", "w"); if (fout == NULL) { printf("fail to open file\n"); return 1; } for (i = 0; i < count; ++i) fprintf(fout, "%ld %s %d\n", minlist[i].no, minlist[i].name, minlist[i].score); fclose(fout); return 0; } int findMinlist(STU s[], int n, STU t[]) { int i, k, min_score; min_score = s[0].score; for (i = 1; i < n; ++i) if (s[i].score < min_score) min_score = s[i].score; k = 0; for (i = 0; i < n; ++i) if (s[i].score == min_score) { t[k] = s[i]; ++k; } return k; }
#include <stdio.h> #include <string.h> #include <stdlib.h> #define N 10 typedef struct { long int id; char name[20]; float objective; float subjective; float sum; char level[10]; } STU; 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; } 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); } void output(STU s[], int n) { FILE *fout; int i; 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); 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); } void process(STU s[], int n) { int i, j, k; STU temp; for (i = 0; i < n; ++i) { s[i].sum = s[i].objective + s[i].subjective; } for (i = 0; i < n; i++) { for (k = 0; k < n - 1 - i; k++) { if (s[k].sum < s[k + 1].sum) { temp = s[k]; s[k] = s[k + 1]; s[k + 1] = temp; } } } j = n / 10; for (i = 0; i < j; i++) { strcpy(s[i].level, "优秀"); } k = n / 2; for (i = j; i < k; ++i) { strcpy(s[i].level, "合格"); } for (i = k; i < n; i++) { strcpy(s[i].level, "不合格"); } }
#include <stdio.h> #include <stdlib.h> #include <time.h> #define N 81 #define M 5 typedef struct { long int id; char name[20]; char banji[60]; } STU; int main() { int i, j; STU x[N], ran[M]; FILE *fin, *fout; fin = fopen("list.txt", "r"); if (fin == NULL) { printf("fail to open list.txt\n"); return 1; } for (i = 1; i <= N; i++) { fscanf(fin, "%ld %s %s", &x[i].id, x[i].name, x[i].banji); } fclose(fin); srand(time(0)); j = rand() % (80) + 1; for (i = 0; i < M; i++) { ran[i] = x[j]; j = rand() % (80) + 1; } fout = fopen("lucky.txt", "w"); if (fout == NULL) { printf("fail to open file\n"); return 1; } for (i = 0; i < M; i++) { fprintf(fout, "%ld %s %s\n", ran[i].id, ran[i].name, ran[i].banji); printf("%ld %s %s\n", ran[i].id, ran[i].name, ran[i].banji); } fclose(fout); return 0; }