https://leetcode.com/problems/jump-game/

interview_prep/algorithm/java/src/main/java/hoa/can/code/gg/Jumping.java

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+package hoa.can.code.gg;
+
+import java.util.Arrays;
+
+/**
+ * https://leetcode.com/problems/jump-game/
+ */
+public class Jumping {
+    final static int NO_WAY = Integer.MAX_VALUE;
+    public static boolean canJump(int[] nums) {
+        int[] memo = new int[nums.length];
+        Arrays.fill(memo, -1);
+        return (minJumps(nums, 0, nums.length - 1, memo) > -1);
+    }
+    private static int minJumps(int steps[], int begin, int dest, int[] memo) {
+        if (begin == dest)
+            return 0;
+        if (steps[begin] == 0)
+            return NO_WAY;
+
+        int minJump = NO_WAY;
+        for (int step = steps[begin]; step >= 1; --step) {
+            if (begin + step <= dest) {
+                minJump = Math.min(minJump, 1 + minJumps(steps, begin + step, dest, memo));
+            }
+        }
+        return memo[begin] = minJump;
+    }
+}

interview_prep/algorithm/java/src/test/java/hoa/can/code/JumpingTest.java

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+package hoa.can.code;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static hoa.can.code.gg.Jumping.canJump;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class JumpingTest {
+    @Test
+    @DisplayName("ok")
+    public void yes() {
+        assertEquals(true, canJump(new int[]{2, 3, 1, 1, 4}));
+        assertEquals(true, canJump(new int[]{1, 3, 5, 8, 9, 2, 6, 7, 6, 8, 9}));
+    }
+
+    @Test
+    @DisplayName("nope")
+    public void no() {
+        assertEquals(true, canJump(new int[]{0}));
+        assertEquals(true, canJump(new int[]{0,1}));
+    }
+}