13jun23greedyAlgo.ts

// You are given a 0-indexed array of integers nums of length n. You are initially positioned at nums[0].

// Each element nums[i] represents the maximum length of a forward jump from index i. In other words, if you are at nums[i], you can jump to any nums[i + j] where:

//     0 <= j <= nums[i] and
//     i + j < n

// Return the minimum number of jumps to reach nums[n - 1]. The test cases are generated such that you can reach nums[n - 1].

//  

// Example 1:

// Input: nums = [2,3,1,1,4]
// Output: 2
// Explanation: The minimum number of jumps to reach the last index is 2. Jump 1 step from index 0 to 1, then 3 steps to the last index.

// Example 2:

// Input: nums = [2,3,0,1,4]
// Output: 2

function jump(nums:number[]):number{
    const n = nums.length;
    let currentMaxReach = nums[0];
    let nextMaxReach = nums[0];
    let minJump = 1;

    for(let i = 1; i < nums.length; i++){
        if(i > currentMaxReach){
            minJump++;
            currentMaxReach = nextMaxReach;
        }
        nextMaxReach = Math.max(nextMaxReach, i+nums[i])
    }
    return minJump;
}