Jump game leetcode problem

Dp Learnings (27 Part Series)

1 House Robber leetcode problem
2 Jump game leetcode problem
… 23 more parts…
3 Jump game II leetcode problem
4 Cherry Pickup II Leetcode Problem
5 Partition Equals Subset Sum Leetcode problem or Subset sum equals to target
6 Maximum Sum Problem GeeksForGeeks
7 Count Palindrome Sub-Strings of a String GeeksForGeeks
8 Length of Longest Common Subsequence (LCS) and Longest common subsequence string leetcode
9 0/1 Knapsack Problem GeeksForGeeks both bounded and Unbounded
10 Shortest distance from source to all other nodes in a Directed Acyclic Graph
11 Coin change Leetcode
12 Coin Change 2 Leetcode
13 Target Sum or Partition with given difference Leetcode
14 Rod cutting Problem (similar to unbounded knapsack)
15 Length of longest common substring
16 Longest Palindromic subsequence (Same as Lcs)
17 Minimum Insertion steps needed to make a string palindrome (Same as LCS)
18 Minimum number of Insertion and deletion needed to convert String A to String B or make both the strings equal (same as lcs)
19 Shortest Common Super-sequence Leetcode (Same as Lcs string)
20 Distinct Subsequence Leetcode
21 Partition with given difference
22 Two best non overlapping events
23 Longest increasing subsequence
24 Edit distance
25 Maximum product subarray
26 Target sum
27 Maximum Multiplication Score

Problem
You are given an integer array nums. You are initially positioned at the array’s first index, and each element in the array represents your maximum jump length at that position.

Return true if you can reach the last index, or false otherwise.

Example 1:

Input: nums = [2,3,1,1,4]
Output: true
Explanation: Jump 1 step from index 0 to 1, then 3 steps to the last index.

Solution: Dp memoization (top down approach)

class Solution {
    public boolean canJump(int[] nums) {
        int dp[] = new int[nums.length];
        Arrays.fill(dp,-1);//intialize with -1 for univisted index
        return jumpToEnd(0,nums,dp);
    }
    public boolean jumpToEnd(int index, int [] nums,int dp[]){
    //base case
        if(index>= nums.length-1) return true;// if we are able to reach to last index or go beyond
        if(dp[index]!=-1) return dp[index]==1;// if this index has already been explored then simple return the result
        for(int jump = 1;jump<=nums[index];jump++){//we can jump atleat 1 step/index ( given nums[index]>=1) and atmost nums[index] steps/indexes
            if(jumpToEnd(index+jump,nums,dp)) {//going to index+jump = newindex, if the newindex is last index or beyond then return true;
                dp[index] = 1;
                return true;
            }
        }
        dp[index] =0;
        return false;//otherwise we are not able to reach to last index even after trying all the steps
    }
}

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Dp Learnings (27 Part Series)

1 House Robber leetcode problem
2 Jump game leetcode problem
… 23 more parts…
3 Jump game II leetcode problem
4 Cherry Pickup II Leetcode Problem
5 Partition Equals Subset Sum Leetcode problem or Subset sum equals to target
6 Maximum Sum Problem GeeksForGeeks
7 Count Palindrome Sub-Strings of a String GeeksForGeeks
8 Length of Longest Common Subsequence (LCS) and Longest common subsequence string leetcode
9 0/1 Knapsack Problem GeeksForGeeks both bounded and Unbounded
10 Shortest distance from source to all other nodes in a Directed Acyclic Graph
11 Coin change Leetcode
12 Coin Change 2 Leetcode
13 Target Sum or Partition with given difference Leetcode
14 Rod cutting Problem (similar to unbounded knapsack)
15 Length of longest common substring
16 Longest Palindromic subsequence (Same as Lcs)
17 Minimum Insertion steps needed to make a string palindrome (Same as LCS)
18 Minimum number of Insertion and deletion needed to convert String A to String B or make both the strings equal (same as lcs)
19 Shortest Common Super-sequence Leetcode (Same as Lcs string)
20 Distinct Subsequence Leetcode
21 Partition with given difference
22 Two best non overlapping events
23 Longest increasing subsequence
24 Edit distance
25 Maximum product subarray
26 Target sum
27 Maximum Multiplication Score

原文链接：Jump game leetcode problem