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28 lines
768 B
28 lines
768 B
#include <bits/stdc++.h>
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using namespace std;
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typedef pair<int, int> PII;
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#define x first
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#define y second
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const int N = 5010;
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PII a[N]; // 南岸和北岸的一对友好城市的坐标
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int f[N]; // 记录以f[i]为结尾的一对友好城市时的，不产生交叉的最多城市对数
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int n; // n组友好城市
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int res;
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int main() {
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cin >> n;
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for (int i = 1; i <= n; i++) cin >> a[i].x >> a[i].y;
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sort(a + 1, a + 1 + n); // PII默认按第一维度first进行排序
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// LIS
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for (int i = 1; i <= n; i++) {
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f[i] = 1;
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for (int j = 1; j < i; j++)
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if (a[i].y > a[j].y)
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f[i] = max(f[i], f[j] + 1);
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res = max(res, f[i]);
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}
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printf("%d\n", res);
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return 0;
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} |