最长上升子序列（n·log(n)）

Author: Dev-XYS

Longest-Increasing-Subsequence(n·log(n)).cpp

@@ -0,0 +1,47 @@
+#include <cstdio>
+
+using namespace std;
+
+int n, d[1000010], least[1000010], longest;
+
+int binary_search(int x)
+{
+	int l = 0, r = longest - 1;
+	do
+	{
+		int mid = (l + r) >> 1;
+		if (least[mid] >= x)
+		{
+			r = mid;
+		}
+		else
+		{
+			l = mid + 1;
+		}
+	} while (l < r);
+	return l;
+}
+
+int main()
+{
+	scanf("%d", &n);
+	for (int i = 0; i < n; i++)
+	{
+		scanf("%d", &d[i]);
+	}
+	least[longest++] = d[0];
+	for (int i = 1; i < n; i++)
+	{
+		int l = binary_search(d[i]);
+		if (d[i] > least[l])
+		{
+			least[longest++] = d[i];
+		}
+		else
+		{
+			least[l] = d[i];
+		}
+	}
+	printf("%d", longest);
+	return 0;
+}