2017 ACM-ICPC 亚洲区（南宁赛区）网络赛 L.The Heaviest Non-decreasing Subsequence Problem

#include<cstdio>
using namespace std;

const int MAXN = 2 * 1000000 + 5;

int gt[MAXN], dp[MAXN];

int binarySearch(int l, int r, int val)
{
int mid;
while (l <= r)
{
mid = (l + r) >> 1;
if (dp[mid] <= val) l = mid + 1;
else r = mid - 1;
}
return l;
}

int toLis(int n)
{
int tot = 0;
dp[tot++] = gt[0];
for (int i = 1;i < n;i++)
{
if (gt[i] >= dp[tot - 1])
dp[tot++] = gt[i];
else
{
int pos = binarySearch(0, tot - 1, gt[i]);
dp[pos] = gt[i];
}
}
return tot;
}

int main()
{
int pos = 0;
for (int tmp;scanf("%d", &tmp) == 1;)
{
if (tmp >= 10000)
for (int i = 1;i <= 5;i++)
gt[pos++] = tmp - 10000;
else if (tmp < 0) continue;
else gt[pos++] = tmp;
}
printf("%d\n", toLis(pos));
return 0;
}