1028 人口普查

1028 人口普查

有几个注意的点：
1.cin和cout会超时，用printf和scanf
2.注意一个合格的居民都没有时，只用输出0
3.比较年龄大小可以直接用年份10000+月份100+天，比较方便

#include <iostream>
#include <vector>
#include <map>
#include <algorithm>
using namespace std;

struct people
{
	string name;
	long long age;
	int year;
	int month;
	int day;
};

bool sortbyage(people p1, people p2)
{
	return p1.age < p2.age;
}
int main()
{
	int n;
	scanf("%d", &n);
	vector<people> citizen(n);
	vector<people> real_citizen;
	char c;
	int  j = 0;
	for (int i = 0; i < n; i++)
	{
		//scanf("%s", &citizen[i].name[j]);
		//scanf("%d%c%d%c%d", &citizen[i].year, &c, &citizen[i].month, &c, &citizen[i].day);
		cin >> citizen[i].name >> citizen[i].year >> c >> citizen[i].month >> c >> citizen[i].day;
		//这个非常巧妙的将年龄直接转为数字，可以直接比较
		citizen[i].age = citizen[i].year * 10000 + citizen[i].month * 100 + citizen[i].day;
		//找到有效居民
		if (citizen[i].age>=18140906 && citizen[i].age<=20140906)
		{
			real_citizen.push_back(citizen[i]);
		}

	}
	//排序
	sort(real_citizen.begin(), real_citizen.end(), sortbyage);
	int s = real_citizen.size();
	//这个地方，出现段错误，可能因为一个人都没有，所以s-1越界了，所以要加一个判断
	if (s > 0)
	{
		printf("%d %s %s", s, real_citizen[0].name.c_str(), real_citizen[s - 1].name.c_str());
		//cout << s << " " << real_citizen[0].name << " " << real_citizen[s - 1].name << endl;
	}
	else
		printf("%d", s);
	return 0;
}