30 lines
686 B
C++
30 lines
686 B
C++
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#include <bits/stdc++.h>
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using namespace std;
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typedef long long LL;
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const int N = 110;
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const int M = 1000010;
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int n, ans, finish;
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struct node {
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int l, r;
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} con[M];
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//按右端点排序
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bool cmp(const node &a, const node &b) {
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return a.r <= b.r;
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}
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int main() {
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cin >> n;
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//输入
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for (int i = 1; i <= n; i++) cin >> con[i].l >> con[i].r;
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//排序
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sort(con + 1, con + 1 + n, cmp);
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for (int i = 1; i <= n; i++)
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if (finish <= con[i].l) //如果finish小于遍历于的线段左端点，那么可用。这句话是核心
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ans++, finish = con[i].r; //迭代的过程
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cout << ans << endl;
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return 0;
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}
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