From 092d462e0be625e736380dc104df906f662aaa43 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=EA=B0=95=EB=AF=BC=ED=98=9C?= <alsgp9898@naver.com>
Date: Sun, 27 Oct 2024 16:46:53 +0900
Subject: [PATCH] =?UTF-8?q?feat:=20=EC=A3=BC=EC=8B=9D=20=EA=B0=80=EA=B2=A9?=
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---
 ...74\354\213\235\352\260\200\352\262\251.js" | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 "\354\212\244\355\203\235/\354\243\274\354\213\235\352\260\200\352\262\251.js"

diff --git "a/\354\212\244\355\203\235/\354\243\274\354\213\235\352\260\200\352\262\251.js" "b/\354\212\244\355\203\235/\354\243\274\354\213\235\352\260\200\352\262\251.js"
new file mode 100644
index 0000000..95c84df
--- /dev/null
+++ "b/\354\212\244\355\203\235/\354\243\274\354\213\235\352\260\200\352\262\251.js"
@@ -0,0 +1,64 @@
+// O(N^2) 풀이
+function solution(prices) {
+    // 1. 반복을 돌면서 스택의 마지막 값이 현재 넣을 값보다 크거나 같은 경우에만 집어넣는다.
+        // 1-1. 현재 인덱스의 하위 인덱스의 카운트를 모두 증가시킨다.
+    // 2. 만약 현재 넣을 값이 더 작은 값이면 마지막 원소보다 크거나 같은 값이 될 때까지 pop을 하여 원소를 빼낸다.
+    const stack = [];
+    const answer = [];
+    
+    prices.forEach((price, index) => {
+        answer.push(prices.length - 1 - index);
+    });
+    
+    const logs = [];
+    
+    for(let i = 0; i<prices.length; i++) {
+        const price = prices[i];
+        
+        const lastElem = stack[stack.length - 1] ?? 0;
+        
+        if(lastElem <= price) {
+            stack.push(price);
+        } else {
+            let temp = 0;
+            while(true){
+                const lastElem = stack[stack.length - 1];
+                if(lastElem <= price) break;
+                stack.pop();
+                temp++;
+            }
+            logs.push([i, temp]);
+        }
+    }
+    
+    for(const [index, count] of logs) {
+        for(let i=index-count; i<index; i++) {
+            answer[i]--;
+        }
+    }
+    
+    return answer;
+}
+
+// O(N) 풀이
+function solution(prices) {
+    const answer = [];
+    
+    const stack = [0];
+    
+    for(let i=1; i<prices.length; i++) {
+        while(prices[i] < prices[stack[stack.length - 1]]) {
+            const j = stack.pop();
+        
+            answer[j] = i - j;
+        }
+        stack.push(i)
+    }
+    
+    while(stack.length > 0) {
+        const j = stack.pop();
+        answer[j] = prices.length - 1 - j;
+    }
+    
+    return answer;
+}
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