Create jumpGameII.java

Author: tanglu

jumpGameII.java

@@ -0,0 +1,33 @@
+//O(n) time complexity
+
+public class Solution {
+    public int jump(int[] A) {
+        if(A==null||A.length==0||A.length==1){
+            return 0;
+        }
+        
+        int start = 0;
+        int end   = 0;
+        int jump_times = 0;
+        int max   = 0;
+        
+        
+        while(end<A.length) {
+            max = 0;
+            jump_times++;
+            //find the max can be reached by current scope 
+            for(int i=start;i<=end;i++) {
+                if((A[i]+i)>=(A.length-1)) {
+                    return jump_times;
+                }
+                if((A[i]+i)>max) {
+                    max = A[i]+i;
+                }
+            }
+            //update for the next search
+            start = end + 1;
+            end   = max;
+        }
+        return jump_times;
+    }
+}