习题5-8 UVa230-Borrowers

本题可以直接采用模拟的方法，不过要注意输出的规则和格式。**输入SHELVE后输出的顺序也是按照先作者后书名的方式。**其余想记录的地方就是采用substr截取所需数据，很实用。

题目链接：UVa 230

AC代码：

#include 
#include 
#include 
#include 
#include 
using namespace std;

const int maxn = 1000;
struct Book {
	string title, author;
	bool operator < (const Book& a) {
		if (author != a.author)
			return author < a.author;
		return title < a.title;
	}
}book;

vector<Book> b, b_c;
vector<Book>::iterator it;
vector<string> back;
map<string, string> match;

bool cmp(const string& a, const string& b) {
	return match[a] < match[b] || (match[a] == match[b] && a < b);
}
void bo(string title) {
	int n = b.size();
	for (it = b.begin(); it != b.end(); it++)
		if ((*it).title == title) {
			b.erase(it);
			sort(b.begin(), b.end());
			break;
		}
}
void re(string title) {
	int n = b_c.size();
	for (int i = 0; i < b.size(); i++) {  //如果该书已经在图书馆中，则拒绝归还
		if (b[i].title == title)
			return;
	}
	for (int i = 0; i < n; i++)
		if (b_c[i].title == title) {
			book.title = title;
			book.author = b_c[i].author;
			back.push_back(title);  //加入还书数组
			b.push_back(book);
			sort(b.begin(), b.end());
			break;
		}
}
void sh() {
	int n = back.size();
	sort(back.begin(), back.end(), cmp);
	for (int i = 0; !back.empty(); )
		for (int j = 0; j < b.size(); j++)
			if (back[i] == b[j].title) {
				if (j)
					cout << "Put " << b[j].title << " after " << b[j - 1].title << endl;
				else
					cout << "Put " << b[j].title << " first" << endl;
				back.erase(back.begin());
				break;
			}
	cout << "END" << endl;
}

int main() {
	string line, str, op;
	while (getline(cin, line) && line[0] != 'E') {
		int p = line.find('"', 1);
		book.title = line.substr(0, p + 1);
		book.author = line.substr(p + 5);
		b.push_back(book);
		match[book.title] = book.author;
	}
	sort(b.begin(), b.end());
	b_c = b;
	while (getline(cin, line) && line != "END") {
		if (line[0] == 'S')
			sh();
		else {
			string title = line.substr(7);
			if (line[0] == 'B')
				bo(title);
			else
				re(title);
		}
	}
	return 0;
}