【模拟题 - 日期处理】

【模拟题 - 日期处理】

模拟题之日期处理题

核心思想日期基础知识日期代码模板日期题的小分类(其他的类似）Accept

[KY 19 第几天？][KY222 打印日期][KY258 日期累加][KY111 日期差值][KY108 Day of Week][KY250 日期类]

核心思想

日期问题是一个在模拟题里是一个比较常考的考点， 有多种考法!其中有一个核心思想就是尽量把日期转化成单维的天数

日期基础知识

日期 年月日， y， m， d
年分为闰年和平年， 闰年的判断方法：
year % 400 == 0
year % 4 == 0 && year % 100 != 0
月份， 大月31天， 小月30天
{31, 28/29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}

日期代码模板

//闰平年的判断
bool isleap(int year) {
	if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0))
		return true;
	return false;
}

//天数计算
int sum  = 0;
int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
for (int i = 1; i < m; i++)
			sum += month[i];
if (isleap(y) && m > 2) adays += 1;
sum += d;

日期题的小分类(其他的类似）

1, 求一年中的第几天
2, 给天数求日期
3, 给日期， 加或者减xx天数， 另算日期
4, 给日期， 计算周几
…等等
我相信吃透这几道类型大致就可以告别模拟题-日期类

KY19 今年的第几天？
KY222 打印日期
KY258 日期累加
KY111 日期差值
KY108 Day of Week
KY250 日期类

Accept [KY 19 第几天？]

#include 
using namespace std;

int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int year, mon, day;
int main() {
	while (cin >> year >> mon >> day) {
		int sum = 0;
		if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0)) {
			if (mon > 2) sum += 1;
		}
		for (int i = 1; i < mon; i++) sum += month[i]; 
		cout << sum+day << endl;
	}
	return 0;
} 

[KY222 打印日期]

#include 
using namespace std;

int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int year, days;
int main() {
	while (cin >> year >> days) {
		int mon = 1;
		bool tag = false;
		if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0)) {
			month[2] += 1; 
			tag = true;
		}
		for (int i = 1; i <= 12; i++) {
			if (days > month[i]) {
				days -= month[i];
				mon += 1;
			} else {
				break;
			}
		}
		if (tag)
			month[2] -= 1;
		printf("%4d-%02d-%02dn", year, mon, days);
	}
	return 0;
} 

[KY258 日期累加]

#include 
using namespace std;

int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int year, mon, day, acdays;
bool isleap(int year) {
	if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0))
		return true;
	return false;
}
int main() {
	int m; cin >> m;
	for (int j = 0; j < m; j++) {
		month[2] = 28;
		int yk = 365;
		cin >> year >> mon >> day >> acdays;
		int sum = 0;
		if (isleap(year) && mon > 2) {
			month[2] = 29;
			yk = 366;
		}
		for (int i = 1; i < mon; i++) {
			sum += month[i];
		}
		sum += (day + acdays);
		while (sum > yk) {
			year += 1;
			sum -= yk;
			if (isleap(year)) 
				yk = 366;
			else yk = 365;
		}
		int index = 1;
		while (sum > month[index]) {
			sum -= month[index];
			index ++;
			if (index == 2 && isleap(year)) month[index] = 29;
			else if (index == 2 && !isleap(year)) month[index] = 28;
		}
		printf("%4d-%02d-%02dn", year, index, sum);
	}
	return 0;
} 

[KY111 日期差值]

#include 
using namespace std;
int ay,by,am,bm,ad,bd;
int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

bool isleap(int year) {
	if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0))
		return true;
	return false;
}
int main() {
	while (scanf("%4d%2d%2d%4d%2d%2d", &ay, &am, &ad, &by, &bm, &bd) != EOF) {
		if (ay <= by) {
			int adays = 0;
			for (int i = 1; i < am; i++)
				adays += month[i];
			if (isleap(ay) && am > 2) adays += 1;
			adays += ad;
			
			int bdays = 0;
			while (ay < by) {
				if (isleap(ay)) bdays += 366;
				else bdays += 365;
				ay++;
			}
			for (int i = 1; i < bm; i++)
				bdays += month[i];
			if (isleap(by) && bm > 2) bdays += 1;
			bdays += bd;
			printf("%dn", bdays-adays+1);
		}
		else {
			int bdays = 0;
			for (int i = 1; i < bm; i++)
				bdays += month[i];
			if (isleap(by) && bm > 2) bdays += 1;
			bdays += bd;
			
			int adays = 0;
			while (by < ay) {
				if (isleap(by)) adays += 366;
				else adays += 365;
				by++;
			}
			for (int i = 1; i < am; i++)
				adays += month[i];
			if (isleap(ay) && am > 2) adays += 1;
			adays += ad;
			printf("%dn", adays-bdays);
		}
	} 
	return 0;
}

[KY108 Day of Week]

#include 
using namespace std;

int ay,by,am,bm,ad,bd;
int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

bool isleap(int year) {
	if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0))
		return true;
	return false;
}
int num(string s) {
	if (s == "January") return 1;
	else if  (s == "February") return 2;
	else if  (s == "March") return 3;
	else if  (s == "April") return 4;
	else if  (s == "May") return 5;
	else if  (s == "June") return 6;
	else if  (s == "July") return 7;
	else if  (s == "August") return 8;
	else if  (s == "September") return 9;
	else if  (s == "October") return 10;
	else if  (s == "November") return 11;
	else if  (s == "December") return 12;
	//不是所有的路径都有返回值
	//加一个return 0
	return 0; 
}
void numweek(int w) {
	if (w == 1) cout << "Monday" << endl;
	else if (w == 2) cout << "Tuesday" << endl;
	else if (w == 3) cout << "Wednesday" << endl;
	else if (w == 4) cout << "Thursday" << endl;
	else if (w == 5) cout << "Friday" << endl;
	else if (w == 6) cout << "Saturday" << endl;
	else if (w == 0) cout << "Sunday" << endl;
}
int main() {
	int d, y; string mon; 
	while (cin >> d >> mon >> y) {
		int sum = 0;
		int m = num(mon);
		int ky = 2001;
		while (ky < y) {
			if (isleap(ky)) sum += 366;
			else sum += 365;
			ky++;
		}
		for (int i = 1; i < m; i++)
			sum += month[i];
		if (isleap(y) && m > 2) sum += 1;
		sum += d;
		int week = sum % 7;
		numweek(week);
	} 
	return 0;
}

[KY250 日期类]

#include 
using namespace std;
int month[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

bool isleap(int year) {
	if (year % 400 == 0 || (year % 100 != 0 && year % 4 == 0))
		return true;
	return false;
}
int main() {
	int n; cin >> n; 
	int y, m, d;
	for (int i = 0; i < n; i++) {
		cin >> y >> m >> d;
		month[2] = 28;
		if (isleap(y)) month[2] = 29;
		d++;
		if (d > month[m]) {
			d = 1;
			m += 1;
		}
		if (m > 12) {
			y += 1;
			m = 1;
		} 
		printf("%04d-%02d-%02dn", y, m, d);
	} 
	return 0;
}