48 lines
1012 B
C++
48 lines
1012 B
C++
#include <bits/stdc++.h>
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using namespace std;
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const int N = 1e5 + 10;
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typedef long long LL;
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#define lowbit(x) (x & -x)
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int n, a[N];
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int b[N], bl;
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LL f[N], tr[N];
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void add(int x, LL c) {
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// 放是往上放
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for (; x <= bl; x += lowbit(x)) tr[x] = max(tr[x], c);
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}
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LL query(int x) {
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// 查是往下查
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LL res = 0;
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for (; x; x -= lowbit(x)) res = max(res, tr[x]);
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return res;
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}
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int main() {
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scanf("%d", &n);
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for (int i = 0; i < n; i++) {
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scanf("%d", a + i);
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b[i] = a[i];
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}
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// 离散化
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sort(b, b + n);
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bl = unique(b, b + n) - b; // 此处bl的含义是b.size()
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for (int i = 0; i < n; i++) {
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int x = lower_bound(b, b + bl, a[i]) - b + 1;
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f[i] = query(x - 1) + a[i];
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add(x, f[i]);
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}
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// 方法1：
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LL res = 0;
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for (int i = 0; i < n; i++) res = max(res, f[i]);
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printf("%lld\n", res);
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// 方法2：
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// printf("%lld\n", query(bl));
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return 0;
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} |