class Solution {
public boolean checkPossibility(int[] nums) {
int l = nums.length,t=0,x=0;
for (int i=1;i<l;i++){
if (nums[i-1]> nums[i]){
t++;
x=i;
}
}
if (t>1) return false;
if (t==0) return true;
if (x == 1) return true;
if (x== l-1) return true;
return (nums[x-2] <= nums[x] || nums[x-1]<=nums[x+1]);
}
}