max height ladder possible from given no. of blocks - O(logn)

Author: NirmalSilwal

CodingBlocks Training/Day14/maxHeightLadder.java

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+package Lecture14;
+
+public class maxHeightLadder {
+
+	public static void main(String[] args) {
+
+		int totalBlocks = 20;
+		System.out.println(maxHeight(totalBlocks));
+
+		System.out.println(maxHeight(21));
+		System.out.println(maxHeight(100));
+		System.out.println(maxHeight(1));
+		System.out.println(maxHeight(0));
+		System.out.println(maxHeight(6));
+		System.out.println(maxHeight(7));
+	}
+
+	// make ladder of maximum height possible with given number of blocks
+	public static int maxHeight(int n) {
+		if (n < 1) {
+			return -1;
+		}
+		int temp = n;
+		int blocks = n * (n + 1) / 2;
+
+		while (blocks > temp) {
+			n = n / 2;
+			blocks = n * (n + 1) / 2;
+		}
+		if (((n + 1) * (n + 2) / 2) <= temp) {
+			return n + 1;
+		}
+		return n;
+	}
+}