Arithmetic Subarrays
给一个数组nums,和一个query数组l和r, 求query中的nums是不是等差数列
这个…就是sort了判断
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class Solution { public List<Boolean> checkArithmeticSubarrays(int[] nums, int[] l, int[] r) { List<Boolean> res = new ArrayList<>(); int[] pre = new int[nums.length + 1]; for(int i = 1; i < nums.length + 1; i++) { pre[i] = pre[i-1] + nums[i - 1]; } for(int i = 0; i < l.length; i++) { boolean t = test(nums, l[i], r[i], pre[r[i]+1] - pre[l[i]]); res.add(t); } return res; } private boolean test(int[] nums, int l, int r, int sum) { int[] aux = new int[r - l + 1]; int k = 0; for(int i = l; i <= r; i++) { aux[k++] = nums[i]; } Arrays.sort(aux); int d = aux[1] - aux[0]; for(int i = 0; i < r - l; i++) { if(aux[i + 1] - aux[i] != d) return false; } return true; } } |