50 lines
1.7 KiB
C++
50 lines
1.7 KiB
C++
// https://www.luogu.com.cn/problem/P2010
|
||
#include <bits/stdc++.h>
|
||
|
||
using namespace std;
|
||
|
||
int months[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
|
||
|
||
//是不是回文字符串
|
||
bool isHW(string s) {
|
||
string t = s;
|
||
reverse(t.begin(), t.end());
|
||
return s == t;
|
||
}
|
||
//通过年月日的整数类型值，构建出一个字符串的年月日
|
||
string build(int year, int month, int date) {
|
||
char x[18]; //不太会使用这个char数组，因为最后一个位置需要放置\0,所以需要开大一点点
|
||
sprintf(x, "%04d%02d%02d", year, month, date); //拼接出一个字符串
|
||
return x; //将字符数组转为字符串，直接赋值即可
|
||
}
|
||
|
||
int cnt;
|
||
int main() {
|
||
string st, ed;
|
||
cin >> st >> ed;
|
||
|
||
int y1 = stoi(st.substr(0, 4)); //截取字符串，字符串转数字
|
||
int y2 = stoi(ed.substr(0, 4));
|
||
|
||
//枚举所有可能年份
|
||
for (int i = y1; i <= y2; i++)
|
||
// 枚举月份
|
||
for (int j = 1; j <= 12; j++)
|
||
//构建所有可能的日期
|
||
for (int k = 1; k <= 31; k++) {
|
||
//闰年的话，二月份的日期不太一样
|
||
int maxd = months[j - 1];
|
||
if (k > maxd) break; //越界的日期没有意义
|
||
//合法日期，构建成字符串
|
||
string s = build(i, j, k);
|
||
|
||
//与范围字符串st,ed进行比较，如果不在范围内，continue
|
||
if (s < st || s > ed) continue;
|
||
|
||
//判断是不是回文
|
||
if (isHW(s)) cnt++;
|
||
}
|
||
//输出
|
||
printf("%d\n", cnt);
|
||
return 0;
|
||
} |