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#include <stdio.h> #include <stdlib.h> typedef struct { int id; char name[50]; int yield; } OrangeFarm; int main() { OrangeFarm new_farm; FILE *fp; printf("---廉江红橙产地数据追加---\n"); printf("请输入新增产地信息（格式：ID 名称 产量）：\n"); if(scanf("%d %s %d", &new_farm.id, new_farm.name, &new_farm.yield) != 3){ printf("输入格式错误。\n"); return 1; } fp = fopen("farms.txt", "a"); if(fp == NULL){ printf("错误：无法打开文件进行追加！\n"); return 1; } fprintf(fp,"%d %s %d\n", new_farm.id, new_farm.name, new_farm.yield); fclose(fp); printf("\n新纪录已成功追加至farms.txt末尾。\n"); return 0; }
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#include <stdio.h> #include <stdlib.h> #include <string.h> typedef struct { int id; char name[50]; int yield; } OrangeFarm; int main() { OrangeFarm farms[100]; int count = 0; int deleted; char confirm; FILE *fp; fp = fopen("farms.txt","r"); if(fp == NULL){ printf("错误：无法打开farms.txt，请确保文件已存在。\n"); return 1; } while(fscanf(fp,"%d %s %d", &farms[count].id, farms[count].name, &farms[count].yield) == 3){ count++; } fclose(fp); if(count == 0){ printf("数据库为空，无数据可删除。\n"); return 0; } printf("---当前廉江红橙产地列表---\n"); int i; for(i = 0; i < count; i++){ printf("[%d] %-12s", farms[i].id, farms[i].name); if((i + 1) % 3 == 0){ printf("\n"); // 每行输出3个后换行 } } printf("\n---------------------------\n"); printf("请输入要删除的产地ID："); scanf("%d", &deleted); int targetIndex = -1; for(i = 0; i < count; i++){ if(farms[i].id == deleted){ targetIndex = i; break; } } if(targetIndex == -1){ printf("错误：未找到ID为%d的记录。\n", deleted); return 0; } printf("拟删除记录详情：\n"); printf("ID：%d|名称：%s|产量：%d吨\n", farms[targetIndex].id, farms[targetIndex].name, farms[targetIndex].yield); printf("警告：此操作不可撤回！确定删除吗？(y/n):"); getchar(); scanf("%c", &confirm); if(confirm != 'y' && confirm !='Y'){ printf("操作已安全取消。\n"); return 0; } for(i = targetIndex; i < count - 1; i++){ farms[i] = farms[i + 1]; } count--; fp = fopen("farms.txt","w"); if(fp == NULL){ printf("系统错误：无法更新文件数据。\n"); return 1; } for(i = 0; i < count; i++){ fprintf(fp,"%d %s %d\n", farms[i].id, farms[i].name, farms[i].yield); } fclose(fp); printf("成功：ID为%d的记录已从系统中彻底删除。\n", deleted); return 0; }
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#include <stdio.h> #include <stdlib.h> #include <string.h> typedef struct { int id; char name[50]; int yield; } OrangeFarm; int main() { OrangeFarm farms[100]; int count = 0; int targetId, choice; FILE *fp; fp = fopen("farms.txt","r"); if(fp == NULL){ printf("错误：无法打开farms.txt，请确保文件已存在。\n"); return 1; } while(fscanf(fp,"%d %s %d", &farms[count].id, farms[count].name, &farms[count].yield) == 3){ count++; } fclose(fp); if(count == 0){ printf("数据库为空，请先添加数据。\n"); return 0; } printf("---当前系统内的产地ID列表---\n"); int i; for(i = 0; i < count; i++){ printf("[%d] %-12s", farms[i].id, farms[i].name); // %-12s 保证名称左对齐 if((i + 1) % 3 == 0){ printf("\n"); // 每行输出3个后换行 } } printf("\n---------------------------\n"); printf("请输入您想要修改的产地ID："); scanf("%d", &targetId); int index = -1; for(i = 0; i < count; i++){ if(farms[i].id == targetId){ index = i; break; } } if(index == -1){ printf("未找到ID为%d的记录。\n", targetId); return 0; } printf("\n已锁定产地ID：%s（产量：%d吨）\n", farms[index].name, farms[index].yield); printf("1.修改产地名称\n"); printf("2.修改预计产量\n"); printf("3.取消修改\n"); printf("请选择操作（1-3）:"); scanf("%d", &choice); switch(choice){ case 1: printf("请输入新的名称:"); scanf("%d", farms[index].name); break; case 2: printf("请输入新的产量（吨）:"); scanf("%d", &farms[index].yield); break; case 3: printf("操作已取消。\n"); return 0; default: printf("非法输入，操作终止。\n"); return 0; } fp = fopen("farms.txt","w"); if(fp == NULL){ printf("回写文件失败！\n"); return 1; } for(i = 0; i < count; i++){ fprintf(fp,"%d %s %d\n", farms[i].id, farms[i].name, farms[i].yield); } fclose(fp); printf("ID为%d的记录已从成功更新。\n", targetId); return 0; }
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#include <stdio.h> #include <stdlib.h> typedef struct { int id; char name[50]; int yield; } OrangeFarm; int main() { OrangeFarm temp; int foundCount = 0; int threshold;//阈值 FILE *fp; fp = fopen("farms.txt","r"); if(fp == NULL){ printf("错误：无法打开farms.txt，请确保文件已存在。\n"); return 1; } printf("----------- 廉江红橙产量筛选系统 -----------\n"); printf("请输入产量阈值（吨）:"); if(scanf("%d", &threshold) != 1){ printf("输入无效。\n"); fclose(fp);//记得关文件 return 1; } printf("\n正在查询产量大于%d的产地…\n", threshold); printf("-------------------------------------------\n"); printf("%-10s %-20s %-10s\n", "ID", "产地名称", "预计产量（吨）"); printf("-------------------------------------------\n"); while(fscanf(fp,"%d %s %d", &temp.id, temp.name, &temp.yield) == 3){ if(temp.yield > threshold){ printf("%-10d %-20d %-10d\n", temp.id, temp.name, temp.yield); foundCount++; } } if(foundCount == 0){ printf("未找到产量超过%d吨的记录。\n", threshold); }else{ printf("-------------------------------------------\n"); printf("查询完毕，共找到%d 条记录。\n", foundCount); } fclose(fp); return 0; }
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