这个源程序怎么写啊，完全不会
1.输入所有同学同一门课程的成绩
2.找出成绩的最高分
3.找出成绩的最低分
4.求出成绩的平均分
5.统计成绩中任意一个分数段的学生人数
6.将最低分放在所有成绩的第一位（换成最高分也可以）
7.输出所有成绩
要求：（1）编写的程序要体现出函数、数组的应用。
（2）程序演示要体现上述功能。
代码如下：
#include<stdio.h>
#define MAX 100
int FindMax(int a[],int n) //输入参数为数组及其长度
{
int max = a[0];
for (int i = 0; i < n; i++)
if (a[i] > max)
max = a[i];
return max; //函数返回值为数组最大值
}
int FindMin(int a[], int n) //输入参数为数组及其长度
{
int min = a[0];
for (int i = 0; i < n; i++)
if (a[i] < min)
min = a[i];
return min; //函数返回值为数组最小值
}
double average(int a[], int n)
{
int sum=0;
double ave;
for (int i = 0; i < n; i++)
sum += a[i];
ave = (double)sum / n;
return ave;//函数返回值为数组平均值
}
int sta_num(int a[], int n)
{
int sta_min, sta_max,count=0;
printf("请输入要统计的分数段（用空格隔开，如：20 90 表示统计20到90分数段）：");
scanf_s("%d %d", &sta_min, &sta_max);
for (int i = 0; i < n; i++)
if (a[i] >= sta_min && a[i] <= sta_max)
count++;
return count;
}
void PutMinFirst(int a[], int n)
{
for(int i=0;i<n-1;i++) //冒泡排序将分数从小到大排序
for(int j=0;j<n-1-i;j++)
if (a[j] > a[j + 1])
{
int temp;
temp = a[j];
a[j] = a[j + 1];
a[j + 1] = temp;
}
}
void Print(int a[], int n)
{
for (int i = 0; i < n; i++)
printf("%d\t", a[i]);
}
int main()
{
int n;//同学人数
int a[MAX];//成绩数组
printf("请输入学生人数：");
scanf_s("%d", &n);
printf("请输入%d个学生成绩：",n);
for (int i = 0; i < n; i++)
scanf_s("%d", &a[i]);//输入n个同学的成绩
printf("max=%d\n", FindMax(a, n)); //求最大数并输出
printf("min=%d\n", FindMin(a, n)); //求最小数并输出
printf("average=%lf\n", average(a, n)); //求平均数并输出
printf("该分数段人数=%d\n", sta_num(a, n)); //求某分数段并输出其人数
PutMinFirst(a, n); //冒泡排序将分数从小到大排序
Print(a, n); //求某分数段并输出其人数
return 0;
}
参考一下
#include<iostream>
#include<fstream>
#include<vector>
#include<string>
#include<algorithm>
#include<Windows.h>
using namespace std;
class Student //学生类
{
public:
Student( string name, int id, string sex)
{
this->name = name;
this->id = id;
this->sex = sex;
}
string name;
int id;
string sex;
};
class Grade //课程类
{
public:
string English;
string Math;
string C_plus;
string Analog_circuit;
string Sports;
string Matlab;
string Data_structure;
string Physical;
};
class Score : public Grade,virtual public Student //成绩类
{
public:
Score(string name, int id, string sex, float English_score, float Math_score, float C_plus_score, float Analog_circuit_score, float Sports_score, float Matlab_score, float Data_structure_score, float Physical_score) :Student(name, id, sex)
{
this->English_score = English_score;
this->Math_score = Math_score;
this->C_plus_score = C_plus_score;
this->Analog_circuit_score = Analog_circuit_score;
this->Sports_score = Sports_score;
this->Matlab_score = Matlab_score;
this->Data_structure_score = Data_structure_score;
this->Physical_score = Physical_score;
GPA = (English_score + Math_score + C_plus_score + Analog_circuit_score + Sports_score + Matlab_score + Data_structure_score + Physical_score) / 8.0;
}
float English_score;
float Math_score;
float C_plus_score;
float Analog_circuit_score;
float Sports_score;
float Matlab_score;
float Data_structure_score;
float Physical_score;
float GPA;
};
class stusystem
{
public:
stusystem() //打开文件
{
ifstream ifs("学生成绩.txt", ios::in);
if (ifs.is_open() != NULL)
{
string name, sex;
int id;
float English_score;
float Math_score;
float C_plus_score;
float Analog_circuit_score;
float Sports_score;
float Matlab_score;
float Data_structure_score;
float Physical_score;
float GPA; //说实话你设的这变量名真的长
while (ifs >> name >> id >> sex >> English_score >> Math_score >> C_plus_score >> Analog_circuit_score >> Sports_score >> Matlab_score >> Data_structure_score >> Physical_score)
{
Score s(name , id , sex , English_score , Math_score , C_plus_score , Analog_circuit_score , Sports_score , Matlab_score , Data_structure_score , Physical_score);
a.push_back(s);
}
}
else
{
cout << "不存在该文件" << endl;
}
}
vector<Score>a;
void Save(); //保存
void Add(); //添加
void AddAgain(); //再度添加
void Del(); //删除
void Find(); //查找菜单
void Findname(); //查找名字
void Findid(); //查找学号
void Sort(); //排序
void Remake(); //重新编辑
void Print(); //打印
void mainmenu() //主菜单
{
system("cls");
cout << "____________________________________________" << endl;
cout << "| |" << endl;
cout << "| 添加学生信息 1 |" << endl;
cout << "| 查找学生信息 2 |" << endl;
cout << "| GPA排名 3 |" << endl;
cout << "| 修改学生信息 4 |" << endl;
cout << "| 删除学生信息 5 |" << endl;
cout << "| 打印学生信息 6 |" << endl;
cout << "| 退出系统 0 |" << endl;
cout << "| |" << endl;
cout << "--------------------------------------------" << endl;
cout << "请输入你的选择:";
int x;
cin >> x;
switch (x)
{
case 1:Add(); break;
case 2:Find(); break;
case 3:Sort(); break;
case 4:Remake(); break;
case 5:Del(); break;
case 6:Print(); break;
case 0:Save(); break;
default:cout << "输入错误，请重新输入\n"; Sleep(1000); mainmenu(); break;
}
}
};
void stusystem::Save() //保存文件
{
ofstream ofs("学生成绩.txt", ios::out);
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
ofs << (*i).name << "\t" << (*i).id << "\t" << (*i).sex << "\t" << (*i).English_score << "\t" <<
(*i).Math_score << "\t" << (*i).C_plus_score << "\t" << (*i).Analog_circuit_score << "\t" << (*i).Sports_score
<< "\t" << (*i).Matlab_score << "\t" << (*i).Data_structure_score << "\t" << (*i).Physical_score << "\t" << (*i).GPA;
}
ofs.close();
}
void stusystem::Add() //添加
{
system("cls");
int flag;
cout << "请输入学生信息：" << endl;
string name, sex;
int id;
float eng, math, cplus, mndl, ty, matlab, sjjg, dw;
while (1)
{
cout << "姓名：";
cin >> name;
cout << "学号：";
cin >> id;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
if ((*i).id == id)
{
cout << "此同学信息已经存在，请重新输入";
Sleep(700);
Add();
}
}
cout << "性别：";
cin >> sex;
do {
flag = 0;
cout << "英语学分：";
cin >> eng;
if (eng > 5.0 || eng < 0) {
cout << " 对不起，请输入0-5.0之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "高数学分：";
cin >> math;
if (math > 5.00 || math < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "C++学分：";
cin >> cplus;
if (cplus > 5.00 || cplus < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "模拟电路学分：";
cin >> mndl;
if (mndl > 5.00 || mndl < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "体育学分：";
cin >> ty;
if (ty > 5.00 || ty < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "Matlab学分：";
cin >> matlab;
if (matlab > 5.00 || matlab < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "数据结构学分：";
cin >> sjjg;
if (sjjg > 5.00 || sjjg < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
do {
flag = 0;
cout << "大学物理学分：";
cin >> dw;
if (dw > 5.00 || dw < 0) {
cout << " 对不起，请输入0-5.00之间的数字！！\n";
}
else {
flag = 1;
}
} while (flag == 0);
Score s(name, id, sex, eng, math, cplus, mndl, ty, matlab, sjjg, dw);
a.push_back(s); //vector头文件中的push_back操作符，意思是插入到表尾
Save();
cout << "添加成功" << endl;
AddAgain();
}
}
void stusystem::AddAgain()
{
cout << "是否继续添加学生成绩信息？(y/n)" << endl;
char sign = '0';
cin >> sign;
switch (sign) {
case'y':
case'Y':
Add(); break;
case'n':
case'N':
mainmenu(); break;
default:cout << "输入错误，请重新输入\n"; Sleep(1000); AddAgain(); break;
}
}
void stusystem::Find()
{
system("cls");
cout << "查找学生成绩：" << endl;
cout << "请选择查询方式：" << endl;
cout << "1-姓名查询" << endl << "2-学号查询" << endl;
int x = 0;
cin >> x;
switch (x)
{
case 1:
Findname(); break;
case 2:
Findid(); break;
}
}
void stusystem::Findname()
{
string s;
bool flag = false; //异常解决方案
cout << "请输入需查找的学生姓名：";
cin >> s;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
if ((*i).name == s)
{
flag = true;
cout << "学号" << "\t" << "姓名" << "\t" << "性别" << " " << "各科学分" << " " << "英语" << " " << "高等数学"
<< " " << "C++" << " " << "模拟电路" << " " << "体育" << " " << "Matlab"
<< " " << "数据结构" << " " << "大学物理" << " " << "GPA" << endl;
cout << (*i).name << "\t" << (*i).id << "\t" << (*i).sex << "\t \t" << (*i).English_score << "\t" <<
(*i).Math_score << "\t" << (*i).C_plus_score << "\t" << (*i).Analog_circuit_score << "\t" << (*i).Sports_score
<< "\t" << (*i).Matlab_score << "\t" << (*i).Data_structure_score << "\t" << (*i).Physical_score << "\t " << (*i).GPA << endl;
cout << "\n按任意键返回主菜单"; char ch;
cin >> ch; mainmenu();
}
if (flag == false)
{
cout << "查无此人！" << endl;
Findname();
}
}
}
void stusystem::Findid()
{
int y=0;
bool flag = false; //异常解决方案
cout << "请输入需查找的学生学号：";
cin >> y;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
if ((*i).id == y)
{
flag = true;
cout << "学号" << "\t" << "姓名" << "\t" << "性别" << " " << "各科学分" << " " << "英语" << " " << "高等数学"
<< " " << "C++" << " " << "模拟电路" << " " << "体育" << " " << "Matlab"
<< " " << "数据结构" << " " << "大学物理" << " " << "GPA" << endl;
cout << (*i).name << "\t" << (*i).id << "\t" << (*i).sex << "\t \t" << (*i).English_score << "\t" <<
(*i).Math_score << "\t" << (*i).C_plus_score << "\t" << (*i).Analog_circuit_score << "\t" << (*i).Sports_score
<< "\t" << (*i).Matlab_score << "\t" << (*i).Data_structure_score << "\t" << (*i).Physical_score << "\t " << (*i).GPA << endl;
cout << "\n按任意键返回主菜单"; char ch;
cin >> ch; mainmenu();
}
if (flag == false)
{
cout << "查无此人！" << endl;
Findid();
}
}
}
void stusystem::Del() //删除
{
cout << "请输入学生的学号" << endl;
int id;
cin >> id;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
if ((*i).id == id)
{
int select;
cout << "学号" << "\t" << "姓名" << "\t" << "性别" << " " << "各科学分" << " " << "英语" << " " << "高等数学"
<< " " << "C++" << " " << "模拟电路" << " " << "体育" << " " << "Matlab"
<< " " << "数据结构" << " " << "大学物理" << " " << "GPA" << endl;
cout << (*i).name << "\t" << (*i).id << "\t" << (*i).sex << "\t \t" << (*i).English_score << "\t" <<
(*i).Math_score << "\t" << (*i).C_plus_score << "\t" << (*i).Analog_circuit_score << "\t" << (*i).Sports_score
<< "\t" << (*i).Matlab_score << "\t" << (*i).Data_structure_score << "\t" << (*i).Physical_score << "\t " << (*i).GPA << endl;
cout << "是否删除？" << endl;
cout << "1.是" << " " << "2.否" << endl;
cin >> select;
switch (select)
{
case 1:
a.erase(i); //以string.h为头文件的删除函数
cout << "删除成功" << endl; Sleep(100); mainmenu(); break;
case 2:
cout << "您未删除" << endl; Sleep(100); mainmenu(); break;
default:cout << "输入错误，将返回主菜单\n"; Sleep(1000); mainmenu(); break;
}
if ((*i).id != id)
{
cout << "查无此人" << endl;
}
}
}
Save();
cout << "\n按任意键返回主菜单"; char ch;
cin >> ch; Sleep(500); return;
}
void stusystem::Remake()
{
system("cls");
cout << "修改学生成绩:" << endl;
cout << "请输入要修改的学生学号：";
int id;
cin >> id;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
if ((*i).id == id)
{
cout << "已找到该学生，请重新输入该学生的信息" << endl;
int ID;
string name, sex;
float eng, math, cplus, mndl, ty, matlab, sjjg, dw;
cout << "姓名:"; cin >> name;
cout << "学号："; cin >> id;
cout << "性别："; cin >> sex;
cout << "英语："; cin >>eng;
cout << "高数："; cin >> math;
cout << "C++:"; cin >>cplus;
cout << "模拟电路:"; cin >> mndl;
cout << "体育："; cin >> ty;
cout << "Matlab:"; cin >> matlab;
cout << "数据结构："; cin >> sjjg;
cout << "大学物理："; cin >> dw;
char c;
cout << "是否保存修改？(y/n)";
cin >> c;
switch (c) {
case'y':
case'Y':
(*i).name = name; (*i).id = id; (*i).sex = sex; (*i).English_score = eng; (*i).Math_score = math;
(*i).C_plus_score = cplus; (*i).Analog_circuit_score = mndl; (*i).Sports_score = ty; (*i).Physical_score = dw; break;
case'n':
case'N':
break;
default:cout << "输入错误，将返回主菜单\n"; Sleep(1000); mainmenu(); break;
}
}
}
Save();
cout << "\n按任意键返回主菜单"; char ch;
cin >> ch; Sleep(500); return;
}
bool mysort(Score a,Score b)//自定义排序规则
{
if (a.GPA == b.GPA) {
return a.id > b.id; //若gpa相同则按学号从小到大排列
}
else {
return a.GPA > b.GPA; //gpa从大到小排
}
}
void stusystem::Sort()
{
system("cls");
if (a.size() == 0)
cout << "文件不存在" << endl;
else {
sort(a.begin(), a.end(), mysort); //排序函数从向量表头至表尾使用自定义mysort规则
cout << "学号" << "\t" << "姓名" << "\t" << "性别" << " " << "各科学分" << " " << "英语" << " " << "高等数学"
<< " " << "C++" << " " << "模拟电路" << " " << "体育" << " " << "Matlab"
<< " " << "数据结构" << " " << "大学物理" << " " << "GPA" << endl;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
cout << (*i).name << "\t" << (*i).id << "\t" << (*i).sex << "\t \t" << (*i).English_score << "\t" <<
(*i).Math_score << "\t" << (*i).C_plus_score << "\t" << (*i).Analog_circuit_score << "\t" << (*i).Sports_score
<< "\t" << (*i).Matlab_score << "\t" << (*i).Data_structure_score << "\t" << (*i).Physical_score << "\t " << (*i).GPA << endl;
}
cout << "\n按任意键返回主菜单"; char ch;
cin >> ch; Sleep(500); return;
}
}
void stusystem::Print()
{
system("cls");
if (a.size() == 0)
cout << "文件不存在" << endl;
else {
cout << "学号" << "\t" << "姓名" << "\t" << "性别" << " " << "各科学分" << " " << "英语" << " " << "高等数学"
<< " " << "C++" << " " << "模拟电路" << " " << "体育" << " " << "Matlab"
<< " " << "数据结构" << " " << "大学物理" << " " << "GPA" << endl;
for (vector<Score>::iterator i = a.begin(); i != a.end(); i++)
{
cout << (*i).name << "\t" << (*i).id << "\t" << (*i).sex << "\t \t" << (*i).English_score << "\t" <<
(*i).Math_score << "\t" << (*i).C_plus_score << "\t" << (*i).Analog_circuit_score << "\t" << (*i).Sports_score
<< "\t" << (*i).Matlab_score << "\t" << (*i).Data_structure_score << "\t" << (*i).Physical_score << "\t " << (*i).GPA << endl;
}
}
cout << "\n按任意键返回主菜单"; char ch;
cin >> ch; Sleep(500); return;
}
int main()
{
stusystem stu;
while (1)
{
stu.mainmenu();
}
return 0;
}
针对每一个问题，找出输入——处理——输出，三个过程
1.输入所有同学同一门课程的成绩（对输入的数据利用数组存储）。 输入为键盘或者文件，处理为输入变成输出的过程，输出为数组存储所输入的数据，下面类似
2.找出成绩的最高分 （使用函数计算数组的最高分——查找算法）
3.找出成绩的最低分（使用函数计算数组的最低分——查找算法）
4.求出成绩的平均分（使用函数计算数组的平均分——遍历每个数组元素，求和，然后求平均值）
5.统计成绩中任意一个分数段的学生人数（使用函数计算分数段的学生人数——遍历每个数组元素，找到符合条件的人就把结果数值加1，即可得到最终结果）
6.将最低分放在所有成绩的第一位（换成最高分也可以）——对数组元素进行排序，如果按照从小到大顺序，排序之后逆序输出，第一个为最大，正序输出，结果为最小
7.输出所有成绩 ——遍历数组元素，对每个元素进行输出