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0031 next-permutation

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	`1`	`+var swap = function (nums, i, j) {`
	`2`	`+ [nums[i], nums[j]] = [nums[j], nums[i]]`
	`3`	`+}`
	`4`	`+`
	`5`	`+/**`
	`6`	`+ * @param {number[]} nums`
	`7`	`+ * @return {void} Do not return anything, modify nums in-place instead.`
	`8`	`+ */`
	`9`	`+var nextPermutation = function (nums) {`
	`10`	`+ let i, n = nums.length;`
	`11`	`+ for (i = n - 1; i > 0; i--)`
	`12`	`+ if (nums[i] > nums[i - 1])`
	`13`	`+ break;`
	`14`	`+`
	`15`	`+ if (i == 0) {`
	`16`	`+ nums.reverse();`
	`17`	`+ // console.log(nums);`
	`18`	`+ return;`
	`19`	`+ }`
	`20`	`+`
	`21`	`+ let min = i, x = nums[i - 1];`
	`22`	`+ for (let j = i + 1; j < n; j++) {`
	`23`	`+ if (nums[j] > x && nums[j] < nums[min])`
	`24`	`+ min = j;`
	`25`	`+ }`
	`26`	`+ swap(nums, i - 1, min);`
	`27`	`+`
	`28`	`+ nums.slice(i, n).sort((a, b) => b - a).concat(nums.slice(0, i));`
	`29`	`+ console.log(nums);`
	`30`	`+};`
	`31`	`+`
	`32`	`+nextPermutation([1,3,2])`

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	`1`	`+const nextPermutation = nums => {`
	`2`	`+ const n = nums.length;`
	`3`	`+ for (let i = n - 2; i >= 0; i--) {`
	`4`	`+ if (nums[i] < nums[i + 1]) {`
	`5`	`+ for (let j = n - 1; j > i; j--) {`
	`6`	`+ if (nums[j] > nums[i]) {`
	`7`	`+ swap(nums, i, j);`
	`8`	`+ reverse(nums, i + 1, n - 1);`
	`9`	`+ return;`
	`10`	`+ }`
	`11`	`+ }`
	`12`	`+ }`
	`13`	`+ }`
	`14`	`+ nums.reverse();`
	`15`	`+};`
	`16`	`+`
	`17`	`+const swap = (nums, i, j) => ([nums[i], nums[j]] = [nums[j], nums[i]]);`
	`18`	`+`
	`19`	`+const reverse = (nums, start, end) => {`
	`20`	`+ while (start < end) {`
	`21`	`+ swap(nums, start++, end--);`
	`22`	`+ }`
	`23`	`+};`
	`24`	`+`
	`25`	`+nextPermutation([1,3,2])`

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	`1`	`+# Next Permutation`
	`2`	`+`
	`3`	`+Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.`
	`4`	`+`
	`5`	`+If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order).`
	`6`	`+`
	`7`	`+The replacement must be in-place and use only constant extra memory.`
	`8`	`+`
	`9`	`+Here are some examples. Inputs are in the left-hand column and its corresponding outputs are in the right-hand column.`
	`10`	`+`
	`11`	`+1,2,3 → 1,3,2`
	`12`	`+`
	`13`	`+3,2,1 → 1,2,3`
	`14`	`+`
	`15`	`+1,1,5 → 1,5,1`
	`16`	`+`
	`17`	`+## More info`
	`18`	`+`
	`19`	`+<https://leetcode.com/problems/next-permutation/>`

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