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// Q1077615.cpp : Defines the entry point for the console application.
//

#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <string>
using namespace std;
struct student 
{
    unsigned long id;
    string name;
    float score;
    student *next; //下一个结点的指针
};

int main()
{
    student head = {-1,"",0};
    head.next = NULL;
    student * p = &head;
    FILE * fp = fopen("Score.txt", "r+");
    while (true)
    {
        unsigned long id;
        char name[100];
        float score;
        if (fscanf(fp, "%ld,%[^,],%f", &id, name, &score) == EOF) break;
        p->next = new student;
        p = p->next;
        p->next = NULL;
        p->id = id;
        p->name = name;
        p->score = score;
    }
    int n;
    while (1)
    {
        cin >> n;
        if (n == 0) break;
        p = head.next;
        while (p)
        {
            if (p->id == n)
            {
                cout << p->name << " " << p->score << endl;
                break;
            }
            p = p->next;
        }
        if (!p || p->id != n)
            cout << "no record!" << endl;
    }
    return 0;
}

210871,张三,95
210872,lisi,92.5
210873,jim zhao,97
210874,han meimei,100
210875,孙行者,80
210876,tony,80
210877,铁柱,94.5
210878,小明,98

完整代码下载
https://download.csdn.net/download/caozhy/12453617