点名系统

#include <iostream>

#include <string>
#include <conio.h>
#include <sstream>
#include <fstream>
#include <map>
#include <deque>
#include <time.h>
using namespace std;

struct stu_node {
	string id;
	string name;
	int punishment;
};

map<string, stu_node> data;
map<string, stu_node>::iterator iter;
deque<string> id;

void XMB() {
	cout << "****************点名系统****************" << endl;
	cout << "1.录入同学信息(会把以前数据全部删掉，格式：学号 姓名 累计惩罚(如无可不写))。" << endl;
	cout << "2.新增同学信息。" << endl;
	cout << "3.必修课点名。" << endl;
	cout << "4.选修课点名。" << endl;
	cout << "5.查看全部同学的累计惩罚。" << endl;
	cout << "6.查看某位同学的累计惩罚。" << endl;
	cout << "7.保存数据。" << endl;
	cout << "8.退出。" << endl;
	cout << "请输入你的选择: ";
}

bool getData(string filename) {
	ifstream inf(filename);
	if(inf == NULL) {
		return false;
	}
	streambuf *strm_buf = cin.rdbuf();
	cin.rdbuf(inf.rdbuf());
	data.clear();
	string line, str;
	stu_node tmp;
	while(getline(cin , line)) {
		istringstream stream(line);
		if(stream >> str) {
			tmp.id = str;
		}else {
			continue;
		}

		if(stream >> str) {
			tmp.name = str;
		}else {
			continue;
		}

		if(stream >> str) {
			tmp.punishment = atoi(str.c_str());
		} else {
			tmp.punishment = 0;
		}
		data.insert(make_pair(tmp.id, tmp));
		id.push_back(tmp.id);
	}
	cin.rdbuf(strm_buf);
	return true;
}

bool saveData(string str) {
	ofstream outf(str.c_str());
	if(outf == NULL) {
		return false;
	}
	streambuf *strm_buf = cout.rdbuf();
	cout.rdbuf(outf.rdbuf());
	for(iter = data.begin(); iter != data.end(); iter++) {
		cout << iter->second.id << " " 
			 << iter->second.name << " "
			 << iter->second.punishment << endl;
	}
	cout.rdbuf(strm_buf);
	return true;
}

int main() {
	char choice = ' ';
	bool ok = true;
	string str;
	stu_node tmp;
	int count;
	int num;
	srand((unsigned)time(NULL));
	getData("data.txt");
	while(ok) {
		system("cls");
		XMB();
		fflush(stdin);
		choice = getch();
		cin.clear();
		cout << choice << endl << endl << endl;
		switch(choice) {
		case '1':
			cout << "请输入文件名: ";
			cin >> str;
			if(getData(str))
				cout << "信息录入成功。" << endl;
			else cout << "信息录入失败。" << endl;
			break;
		case '2':
			cout << "请输入学号:";
			cin >> str;
			if((iter = data.find(str)) != data.end()) {
				cout << "此同学已经存在,信息如下:" << endl;
				cout << "学号\t\t姓名\t累计惩罚" << endl;
				cout << iter->second.id << "\t" 
					 << iter->second.name << "\t"
					 << iter->second.punishment << endl;
			}else {
				tmp.id = str;
				cout << "请输入姓名:";
				cin >> str;
				tmp.name = str;
				tmp.punishment = 0;
				data.insert(make_pair(tmp.id, tmp));
				id.push_back(tmp.id);
				cout << "录入成功." << endl;
			}
			break;
		case '3':
			cout << "现在开始进行必修课点名。输入y/Y代表已到，否则算缺席。" << endl;
			count = data.size() * 0.3 + 1;
			while(count) {
				num = rand() % count;
				str = id.at(num);
				iter = data.find(str);
				id.erase(id.begin() + num);
				id.push_back(str);
				cout << iter->first << " " << iter->second.name << " 在么?(y/n): ";
				fflush(stdin);
				choice = getch();
				cout << choice << endl;
				if(!(choice == 'y' || choice == 'Y'))
					iter->second.punishment += 2;
				count--;
			}
			break;
		case '4':
			cout << "现在开始进行选修课点名。输入y/Y代表已到，否则算缺席。" << endl;
			count = data.size() * 0.3 + 1;
			while(count) {
				num = rand() % count;
				str = id.at(num);
				iter = data.find(str);
				id.erase(id.begin() + num);
				id.push_back(str);
				cout << iter->first << " " << iter->second.name << " 在么?(y/n): ";
				fflush(stdin);
				choice = getch();
				cout << choice << endl;
				if(!(choice == 'y' || choice == 'Y'))
					iter->second.punishment += 2;
				count--;
			}
			break;
		case '5':
			cout << "各同学信息如下：" << endl;
			cout << "学号\t\t姓名\t累计惩罚" << endl;
			for(iter = data.begin(); iter != data.end(); iter++) {
				cout << iter->second.id << "\t" 
					 << iter->second.name << "\t"
					 << iter->second.punishment << endl;
			}
			break;
		case '6':
			cout << "请输入学号: ";
			cin >> str;
			if((iter = data.find(str)) != data.end()) {
				cout << "此同学信息如下:" << endl;
				cout << "学号\t\t姓名\t累计惩罚" << endl;
				cout << iter->second.id << "\t" 
					 << iter->second.name << "\t"
					 << iter->second.punishment << endl;
			}else {
				cout << "此同学信息不存在。" << endl;
			}
			break;
		case '7':
			cout << "请输入文件名: ";
			cin >> str;
			if(saveData(str))
				cout << "保存成功。" << endl;
			else cout << "保存失败。" << endl;
			break;
		case '8':
			ok = false;
			break;
		default:
			cout << "输入错误。" << endl;
		}
		system("pause");
	}
	saveData("data.txt");
	return 0;
}