classSolution{
publicintwiggleMaxLength(int[] nums){
int n = nums.length;if(n <2){
return n;}int up =1;int down =1;for(int i =1; i < n; i++){
if(nums[i]> nums[i -1]){
up = down +1;}elseif(nums[i]< nums[i -1]){
down = up +1;}}return Math.max(up, down);}}