From 057d6b8f89ea5bbef1bb460ce40d9093abd1c3e0 Mon Sep 17 00:00:00 2001 From: fw_qaq Date: Thu, 13 Apr 2023 13:34:46 +0800 Subject: [PATCH] =?UTF-8?q?Update=200746.=E4=BD=BF=E7=94=A8=E6=9C=80?= =?UTF-8?q?=E5=B0=8F=E8=8A=B1=E8=B4=B9=E7=88=AC=E6=A5=BC=E6=A2=AF.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0746.使用最小花费爬楼梯.md | 33 +++++++++++++------- 1 file changed, 22 insertions(+), 11 deletions(-) diff --git a/problems/0746.使用最小花费爬楼梯.md b/problems/0746.使用最小花费爬楼梯.md index 561441fc..f11439c0 100644 --- a/problems/0746.使用最小花费爬楼梯.md +++ b/problems/0746.使用最小花费爬楼梯.md @@ -399,18 +399,29 @@ impl Solution { ### C ```c -int minCostClimbingStairs(int* cost, int costSize){ - //开辟dp数组,大小为costSize - int *dp = (int *)malloc(sizeof(int) * costSize); - //初始化dp[0] = cost[0], dp[1] = cost[1] - dp[0] = cost[0], dp[1] = cost[1]; +#include +int minCostClimbingStairs(int *cost, int costSize) { + int dp[costSize + 1]; + dp[0] = dp[1] = 0; + for (int i = 2; i <= costSize; i++) { + dp[i] = fmin(dp[i - 2] + cost[i - 2], dp[i - 1] + cost[i - 1]); + } + return dp[costSize]; +} +``` - int i; - for(i = 2; i < costSize; ++i) { - dp[i] = (dp[i-1] < dp[i-2] ? dp[i-1] : dp[i-2]) + cost[i]; - } - //选出倒数2层楼梯中较小的 - return dp[i-1] < dp[i-2] ? dp[i-1] : dp[i-2]; +不使用 dp 数组 + +```c +#include +int minCostClimbingStairs(int *cost, int costSize) { + int dpBefore = 0, dpAfter = 0; + for (int i = 2; i <= costSize; i++) { + int dpi = fmin(dpBefore + cost[i - 2], dpAfter + cost[i - 1]); + dpBefore = dpAfter; + dpAfter = dpi; + } + return dpAfter; } ```