这个简单的学生信息系统调试时怎么不能进行查询成绩！！求大佬教教我！！！谢谢
代码如下：
#include<iostream>
#include<iomanip>
#include<cstring>
using namespace std;
struct student
{
char name[20];//姓名
double sum;//总分和平均分
double MT, EN, PH;//各科成绩
long num;//学号
};
int readscore(student stu[])
{
int count=0;//人数
cout.setf(ios::right);
cout << "名字" << setw(5);
cout << "学号" << setw(5);
cout << "数学" << setw(5);
cout << "英语" << setw(5);
cout << "物理" << setw(5);
cout << endl;
for (int i = 0; i < 30; i++)
{
cin >> stu[i].name >> stu[i].num >> stu[i].MT >> stu[i].EN >> stu[i].PH;
if (stu[i].MT <= 0)
break;
count++;
}return count;
}
int getsum(student stu[],int n)
{
double Sum = 0;
for (int i = 0; i < n; i++)
{
stu[i].sum = 0;
stu[i].sum = stu[i].MT + stu[i].EN + stu[i].PH;
Sum = stu[i].sum;
}return Sum;
}
void mppx(student stu[], int n)
{
for (int m = n-1; m >0; m--)
{
int max = 0;
char name[20];//姓名
long num = 0;//学号
double mt = 0;//数学
double en = 0;//英语
double ph = 0;//物理
for (int i = 0; i < m; i++)//排序
{
if (stu[i].sum <stu[i + 1].sum)
{
strcpy_s(name, stu[i].name);
strcpy_s(stu[i].name, stu[i + 1].name);
strcpy_s(stu[i + 1].name, name);
num = stu[i].num;
stu[i].num = stu[i + 1].num;
stu[i + 1].num = num;
mt = stu[i].MT;
stu[i].MT = stu[i + 1].MT;
stu[i + 1].MT = mt;
en = stu[i].EN;
stu[i].EN = stu[i + 1].EN;
stu[i + 1].EN = en;
ph = stu[i].PH;
stu[i].PH = stu[i + 1].PH;
stu[i + 1].PH = ph;
max = stu[i].sum;
stu[i].sum = stu[i + 1].sum;
stu[i + 1].sum = max;
}
}
}
cout.setf(ios::left);
cout << "总成绩表：" << endl;
cout << "排名" << setw(5);
cout << "姓名" << setw(5);
cout << "学号" << setw(5);
cout << "总分" << setw(5);
cout << "高数" << setw(5);
cout << "英语" << setw(5);
cout << "物理" << setw(5);
cout << "平均分" << endl;
for (int j = 0; j < n; j++)
{
cout.setf(ios::left);
cout << j + 1 << setw(5);
cout << stu[j].name << setw(5);
cout << stu[j].num << setw(5);
cout << stu[j].sum << setw(5);
cout << stu[j].MT << setw(5);
cout << stu[j].EN << setw(5);
cout << stu[j].PH << setw(5);
cout << stu[j].sum / 3 << endl;
}
}
int find(student stu[], int n)//查询成绩
{
int a = 0, b = 0;
long num;
cin >> num;
for (int j = 0; j < n; j++)
{
if (num == stu[j].num)
{
b++;
a++;
}
}
if (b != 0)
{
cout.setf(ios::left);
cout << "排名" << setw(5);
cout << "姓名" << setw(5);
cout << "学号" << setw(5);
cout << "总分" << setw(5);
cout << "高数" << setw(5);
cout << "英语" << setw(5);
cout << "物理" << setw(5);
cout << "平均分" << endl;
}
for (int i = 0; i < n; i++)
{
if (num == stu[i].num)
{
cout.setf(ios::left);
cout << i + 1 << setw(5);
cout << stu[i].name << setw(5);
cout << stu[i].num << setw(5);
cout << stu[i].sum << setw(5);
cout << stu[i].MT << setw(5);
cout << stu[i].EN << setw(5);
cout << stu[i].PH << setw(5);
cout << stu[i].sum / 3 << endl;
}
}
if (a == 0)
{
cout << "查无此人！请重新输入：";
return -1;
}
}
int main()
{
student stu[30];
double a;
a = readscore(stu);
cout << "===============================================" << endl; getsum(stu, a);
for (int i = 0; i < a; i++)
{
cout.setf(ios::left);
cout << "姓名" << stu[i].name << setw(5);
cout << "数学" << stu[i].MT << setw(5);
cout << "英语" << stu[i].EN << setw(5);
cout << "物理" << stu[i].PH << endl;
}
cout << "总人数:" << a << endl;
cout << "***********************************************" << endl; mppx(stu, a);
cout << "***********************************************" << endl;
cout << "请输入要查找的学号："<<endl;
find(stu, a);
cout << endl;
return 0;
}
