用C语言改一下#include<iostream> #include<cstring> #include<iomanip> using namespace std; struct student{ char name[20]; int num; //学号 int number; //票数 int Class; char major[30]; char grade[10]; char achievement[200]; }; class votesystem{ private: studentst; int count; //当前元素个数 int size; //哈希表长 public: void InitHashTable(int n); //初始化哈希表 int Hash(charname); //计算哈希地址 void collision(int &s); //冲突，计算下一个地址 int search(char name,int &s); //查找 void insert(charname); //插入 int vote(char*name); //投票 void display(); //显示哈希表 void showvote(int k); //按哈希表下标显示票数 void showrank(); //显示排行榜 };

使用C语言改写该代码如下： ```c #include <stdio.h> #include <string.h> #include <stdlib.h> #define MAX_NAME_LEN 20 #define MAX_MAJOR_LEN 30 #define MAX_GRADE_LEN 10 #define MAX_ACHIEVEMENT_LEN 200 #define HASH_TABLE_SIZE 100 typedef struct student { char name[MAX_NAME_LEN]; int num; //学号 int number; //票数 int Class; char major[MAX_MAJOR_LEN]; char grade[MAX_GRADE_LEN]; char achievement[MAX_ACHIEVEMENT_LEN]; } student; typedef struct HashNode { student st; int flag; //标记该位置是否被占用 } HashNode; typedef struct votesystem { HashNode table[HASH_TABLE_SIZE]; int count; //当前元素个数 } votesystem; void InitHashTable(votesystem *vs) { vs->count = 0; for (int i = 0; i < HASH_TABLE_SIZE; i++) { vs->table[i].flag = 0; } } int Hash(char *name) { int hash_val = 0; for (int i = 0; name[i] != '\0'; i++) { hash_val = (hash_val * 31 + name[i]) % HASH_TABLE_SIZE; } return hash_val; } void collision(int *s) { (*s)++; if (*s == HASH_TABLE_SIZE) { *s = 0; } } int search(votesystem *vs, char *name, int *s) { int hash_val = Hash(name); while (vs->table[hash_val].flag != 0 && strcmp(vs->table[hash_val].st.name, name) != 0) { collision(s); hash_val = Hash(name) + *s; } if (vs->table[hash_val].flag == 0) { return -1; //未找到该元素 } else { return hash_val; } } void insert(votesystem *vs, student st) { if (vs->count == HASH_TABLE_SIZE) { printf("Hash table is full!\n"); } else { int s = 0; int hash_val = Hash(st.name); while (vs->table[hash_val].flag == 1) { collision(&s); hash_val = Hash(st.name) + s; } vs->table[hash_val].st = st; vs->table[hash_val].flag = 1; vs->count++; } } int vote(votesystem *vs, char *name) { int s = 0; int hash_val = search(vs, name, &s); if (hash_val == -1) { printf("Student %s not found!\n", name); return -1; } else { vs->table[hash_val].st.number++; return vs->table[hash_val].st.number; } } void display(votesystem *vs) { for (int i = 0; i < HASH_TABLE_SIZE; i++) { if (vs->table[i].flag == 1) { printf("name: %s, num: %d, number: %d, Class: %d, major: %s, grade: %s, achievement: %s\n", vs->table[i].st.name, vs->table[i].st.num, vs->table[i].st.number, vs->table[i].st.Class, vs->table[i].st.major, vs->table[i].st.grade, vs->table[i].st.achievement); } } } void showvote(votesystem *vs, int k) { if (k >= 0 && k < HASH_TABLE_SIZE && vs->table[k].flag == 1) { printf("name: %s, number: %d\n", vs->table[k].st.name, vs->table[k].st.number); } else { printf("Invalid index!\n"); } } void showrank(votesystem *vs) { student *tmp_st = (student *) malloc(sizeof(student) * vs->count); int tmp_count = 0; for (int i = 0; i < HASH_TABLE_SIZE; i++) { if (vs->table[i].flag == 1) { tmp_st[tmp_count++] = vs->table[i].st; } } for (int i = 0; i < tmp_count - 1; i++) { for (int j = i + 1; j < tmp_count; j++) { if (tmp_st[i].number < tmp_st[j].number) { student tmp = tmp_st[i]; tmp_st[i] = tmp_st[j]; tmp_st[j] = tmp; } } } for (int i = 0; i < tmp_count; i++) { printf("%d. name: %s, number: %d\n", i + 1, tmp_st[i].name, tmp_st[i].number); } free(tmp_st); } int main() { votesystem vs; InitHashTable(&vs); student st1 = {"Tom", 1001, 0, 1, "Computer Science", "Grade 1", "Excellent"}; student st2 = {"Jerry", 1002, 0, 1, "Computer Science", "Grade 1", "Good"}; student st3 = {"Bob", 1003, 0, 1, "Computer Science", "Grade 1", "Average"}; insert(&vs, st1); insert(&vs, st2); insert(&vs, st3); vote(&vs, "Tom"); vote(&vs, "Jerry"); vote(&vs, "Tom"); vote(&vs, "Tom"); display(&vs); showvote(&vs, Hash("Tom")); showrank(&vs); return 0; } ```