Leetcode - Triangle
https://leetcode.com/problems/triangle/
Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.
For example, given the following triangle
[
[2],
[3,4],
[6,5,7],
[4,1,8,3]
]
The minimum path sum from top to bottom is 11 (i.e., 2 + 3 + 5 + 1 = 11).
Note:
Bonus point if you are able to do this using only O(n) extra space, where n is the total number of rows in the triangle.
func minimumTotal(nums [][]int) int {
if len(nums) == 0 {
return 0
}
n := len(nums)
dp := make([][]int, n)
for i := 0; i < len(dp); i++ {
dp[i] = make([]int, i+1)
}
dp[0][0] = nums[0][0]
for i := 1; i < n; i++ {
for j := 0; j < len(dp[i]); j++ {
if j != 0 && j != len(dp[i])-1 {
dp[i][j] = nums[i][j] + min(dp[i-1][j-1], dp[i-1][j])
}
if j == 0 {
dp[i][j] = nums[i][j] + dp[i-1][j]
}
if j == len(dp[i])-1 {
dp[i][j] = nums[i][j] + dp[i-1][j-1]
}
}
}
//fmt.Println("dp: ", dp)
return min(dp[n-1]...)
}
func min(nums ...int) int {
minNum := nums[0]
for _, n := range nums {
if minNum > n {
minNum = n
}
}
return minNum
}
Nov 07, 2021 02:45:44 PM