LeetCode - Jump Game

JumpGame.java

//
public boolean canJump(int[] nums) {
    if(nums.length == 0) return false;
    int i=-1, reach = 0;
    while(i < reach){
        if(reach >= nums.length-1) return true;
        i++;
        reach = Math.max(reach, i+nums[i]);
    }
    return false;
}
    
// 
public boolean canJump(int[] A) {
    if(A==null || A.length==0) return false;
    int reach = 0;
    for(int i=0; i<=reach&&i<A.length; i++){
        int localMax = i+A[i];
        reach = Math.max(localMax, reach);
    }
    if(reach>=A.length-1) return true;
    return false;
}
    
//
public boolean canJump(int[] nums) {
    if(nums == null || nums.length == 0) return false;
    int range = nums[0];
    int i = 0;
    while(i <= range){
        if(range >= nums.length-1) return true;
        if(i + nums[i] > range){
            range = i+ nums[i];
        }
        i++;
    }
    return false;
}