杨辉三角
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
int main(void) { int a[10][10],i,j; for(i=0;i<10;i++) { // for(j=10;j>=i;j--) // printf("%2c",'*');/*两个空格*/ for(j=0;j<=i;j++) //打出直角三角形, { if(i==j||j==0) //给对角线和第一列赋值为1 { a[i][j]=1; } else //剩下内面的值等于上一行的两数之和 { a[i][j]=a[i-1][j]+a[i-1][j-1]; } printf("%3d ",a[i][j]); /*%3d后一个空格*/ if(i==j) //为对角线的时候换行 { printf("\n"); } } } return 0; }
2pingjiang
#include <stdio.h> #include <stdbool.h> #include <stdlib.h> #include <string.h> struct Stuinfo { char ID[4]; char NAME[10]; int Score; }; struct Stuinfo stuInfo[100];//结构体数组 FILE *file;//文件指针,指向物理文件 bool checkId(char Id[]); bool checkId(char Id[]) { bool s = false; for (int i = 0; i < strlen(Id); i++) { if (Id[i] >= '0' && Id[i] <= '9') { s = true; } else { s = false; break; // } } return s; } bool checkName(char name[]); bool checkName(char name[]) { bool s = false; for (int i = 0; i < strlen(name); i++) { if ((name[i] >= 'a' && name[i] <= 'z') || (name[i] >= 'A' && name[i] <= 'Z')) { s = true; } else { s = false; break; // } } return s; } void createDB(); void createDB() { int i = 0;//代表先在录入第i个学生 int m = 0;//录入了多少学生 bool success = 0; while (1) { //学号 printf("请输入第%d个学生的信息\n",i+1); do { printf("请输入学号\n"); char tempId[4]; scanf("%s",tempId); if (checkId(tempId)) { success = 1; strcpy(stuInfo[i].ID, tempId); } else { success = 0; printf("输入的学号有错误\n"); } } while (!success); //姓名 do { printf("请输入姓名\n"); char tempName[10]; scanf("%s",tempName); if (checkName(tempName)) { success = 1; strcpy(stuInfo[i].NAME, tempName); } else { success = 0; } } while (!success); //成绩 do { printf("请输入成绩\n"); int score = 0; scanf("%d",&score); if (score >= 0 && score <=100) { success = 1; stuInfo[i].Score = score; } else { success = 0; } } while (!success); i++; m++; //跳出循环的条件 printf("是继续录入信息请按y或Y\n"); getchar();//截取\n char ch; scanf("%c",&ch); if (ch == 'Y' || ch == 'y') { continue; } else { break; } } //把数据记录到文件 if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","w+")) == NULL) { printf("打开文件失败\n"); } for (int i = 0 ; i < m; i++) { fwrite(&stuInfo[i], sizeof(struct Stuinfo), 1, file);//只是写到缓冲区 } fclose(file);//写到文件上 } void printStuInfo(); void printStuInfo() { if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","r")) == NULL) { printf("打开文件失败\n"); } int n = 0; //代表文件中几条记录 for(int i = 0;fread(&stuInfo[i],sizeof(struct Stuinfo), 1, file);i++ ) { n++; } printf("学号--------姓名-------成绩-----\n"); for(int j = 0;j < n ;j++) { printf("%-10s %-10s %-10d\n",stuInfo[j].ID,stuInfo[j].NAME,stuInfo[j].Score); } printf("------------------------------\n"); fclose(file); } void searchByName(); void searchByName() { int n = 0;//记录文件中有几条记录 if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","r")) == NULL) { printf("打开文件失败\n"); } for (int i = 0;fread(&stuInfo[i],sizeof(struct Stuinfo), 1, file);i++) { n++; } while(1) { printf("请输入你想查找学生的姓名\n"); char temp[10]; scanf("%s",temp); int flag = 0 ; printf("学号--------姓名-------成绩-----\n"); for(int i = 0 ;i < n; i++) { if(strcmp(temp, stuInfo[i].NAME) == 0) { printf("%-10s %-10s %-10d\n",stuInfo[i].ID,stuInfo[i].NAME,stuInfo[i].Score); } else { flag++; } } if(flag == n) { printf("对不起,没查到你需要找到学生\n"); } printf("------------------------------\n"); // printf("按Y或y继续查找\n"); getchar(); char ch; scanf("%c",&ch); if(ch == 'Y' || ch == 'y') { continue; } else { break; } } } void insertInfo(); void insertInfo() { int n = 0;//记录文件中有几条记录 if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","r")) == NULL) { printf("打开文件失败\n"); } for (int i = 0;fread(&stuInfo[i],sizeof(struct Stuinfo), 1, file);i++) { n++; } // int i = 0;//代表先在录入第i个学生 int m = 0;//录入了多少学生 bool success = 0; while (1) { //学号 printf("请输入第%d个学生的信息\n",n+i+1); do { printf("请输入学号\n"); char tempId[4]; scanf("%s",tempId); if (checkId(tempId)) { success = 1; strcpy(stuInfo[i].ID, tempId); } else { success = 0; printf("输入的学号有错误\n"); } } while (!success); //姓名 do { printf("请输入姓名\n"); char tempName[10]; scanf("%s",tempName); if (checkName(tempName)) { success = 1; strcpy(stuInfo[i].NAME, tempName); } else { success = 0; } } while (!success); //成绩 do { printf("请输入成绩\n"); int score = 0; scanf("%d",&score); if (score >= 0 && score <=100) { success = 1; stuInfo[i].Score = score; } else { success = 0; } } while (!success); i++; m++; //跳出循环的条件 printf("是继续录入信息请按y或Y\n"); getchar();//截取\n char ch; scanf("%c",&ch); if (ch == 'Y' || ch == 'y') { continue; } else { break; } } //把数据记录到文件 if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","a+")) == NULL)//追加 { printf("打开文件失败\n"); } for (int i = 0 ; i < m; i++) { fwrite(&stuInfo[i], sizeof(struct Stuinfo), 1, file);//只是写到缓冲区 } fclose(file);//写到文件上 } void deleteByName(); void deleteByName() { int n = 0; if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt", "r")) == NULL) { printf("打开文件失败\n"); } for (int i = 0;fread(&stuInfo[i],sizeof(struct Stuinfo), 1, file);i++) { n++; } // char temp[10]; int i = 0; while(1) { printf("请输入要删除学生的名字\n"); scanf("%s",temp); printf("学号--------姓名-------成绩-----\n"); for (; i < n ; i++) { if (strcmp(stuInfo[i].NAME, temp) == 0) { printf("%-10s %-10s %-10d\n",stuInfo[i].ID,stuInfo[i].NAME,stuInfo[i].Score); if (i == n - 1)//删除最后1个 { } else//删除中间 { for(int j = i;j < n -1;j++) { stuInfo[j] = stuInfo[j+1]; } } n--; i = -1; //找到删除了i 又从0开始遍历,没找到i不用从0开始 } } printf("------------------------------\n"); // printf("按y或Y继续删除\n"); getchar(); char ch; scanf("%c",&ch); if(ch == 'Y' || ch == 'y') { continue; } else { break; } } //把数据记录到文件 if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","w")) == NULL) { printf("打开文件失败\n"); } for (int i = 0 ; i < n; i++) { fwrite(&stuInfo[i], sizeof(struct Stuinfo), 1, file);//只是写到缓冲区 } fclose(file);//写到文件上 } void sortByScore(); void sortByScore() { int n = 0; if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt", "r")) == NULL) { printf("打开失败\n"); } for (int i = 0 ; fread(&stuInfo[i],sizeof(struct Stuinfo), 1, file); i++) { n++; } struct Stuinfo temp; for (int j = 0; j < n -1; j++) { for (int i = 0; i < n - j - 1; i++) { if (stuInfo[i].Score < stuInfo[i+1].Score) { temp = stuInfo[i+1]; stuInfo[i+1] = stuInfo[i]; stuInfo[i] = temp; } } } //把数据记录到文件 if ((file = fopen("/Users/3022/Desktop/code_C/评讲/stuInfo/stu.txt","w")) == NULL) { printf("打开文件失败\n"); } for (int i = 0 ; i < n; i++) { fwrite(&stuInfo[i], sizeof(struct Stuinfo), 1, file);//只是写到缓冲区 } fclose(file);//写到文件上 } int main(int argc, const char * argv[]) { printf("1.创建2.输出3.查找4.插入5.删除6.排序\n"); int w; scanf("%d",&w); while (1) { switch (w) { case 1: { createDB(); break; } case 2: { printStuInfo(); break; } case 3: { searchByName(); break; } case 4: { insertInfo(); break; } case 5: { deleteByName(); break; } case 6: { sortByScore(); break; } default: break; } printf("1~6继续操作:\n1.创建2.输出3.查找4.插入5.删除6.排序\n"); scanf("%d",&w); if(w <=6 && w > 0) { continue; } else { break; } } return 0; }