179. Largest Number

Given a list of non-negative integers nums, arrange them such that they form the largest number and return it.

Since the result may be very large, so you need to return a string instead of an integer.

Example 1:

Input: nums = [10,2]
Output: "210"

Example 2:

Input: nums = [3,30,34,5,9]
Output: "9534330"

Constraints:

• 1 <= nums.length <= 100
• 0 <= nums[i] <= 109

解法

先建立一個陣列，把數字都轉換成字串存入，然後就字串陣列進行降序排序，把最後字串陣列的內容組合便是答案

Golang

func largestNumber(nums []int) string {
    ans := make([]string, len(nums))
    for i, v :=range nums {
        ans[i] = strconv.Itoa(v)
    }
    sort.Slice(ans, func(i, j int) bool {
        return ans[i] + ans[j] > ans[j]+ ans[i]
    })
    if ans[0] == "0" {
        return "0"
    }
    return strings.Join(ans,"")
}