48 lines
1.3 KiB
C++
48 lines
1.3 KiB
C++
// https://www.luogu.com.cn/problem/P2010
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#include <bits/stdc++.h>
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using namespace std;
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//月份日期常数数组
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int months[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
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//判断是不是闰年
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bool LeapYear(int year) {
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return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
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}
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//是不是回文字符串
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bool isHW(string s) {
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string t = s;
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reverse(t.begin(), t.end());
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return s == t;
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}
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int cnt;
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int main() {
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int st, ed;
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cin >> st >> ed;
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int y1 = st / 10000;
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int y2 = ed / 10000;
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//枚举年份
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for (int i = y1; i <= y2; i++)
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// 枚举月份
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for (int j = 1; j <= 12; j++) {
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//枚举日期
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int day = months[j];
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if (LeapYear(i) && j == 2) day = 29; //闰年二月份，共29天
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for (int k = 1; k <= day; k++) {
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int s = i * 10000 + j * 100 + k;
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//与范围字符串st,ed进行比较，如果不在范围内，continue
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if (s < st || s > ed) continue; //日期字符串符合字典序
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//判断是不是回文
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char x[10];
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sprintf(x, "%d", s);
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if (isHW(x)) cnt++;
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}
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}
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//输出
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printf("%d\n", cnt);
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return 0;
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} |