[BOJ] 좋다 / 골드4 / 45분

https://www.acmicpc.net/problem/1253

Author: YoonYn9915

YoonYn9915/sort/2025-01-20-[백준]-#1253-좋다.py

@@ -0,0 +1,26 @@
+N = int(input())
+arr = list(map(int, input().split()))
+
+arr_sorted = sorted(arr)
+
+answer = 0
+
+for i in range(N):
+    start = 0
+    end = len(arr_sorted) - 1
+
+    while start < end:
+        if arr_sorted[start] + arr_sorted[end] == arr_sorted[i]:
+            if start == i:
+                start += 1
+            elif end == i:
+                end -= 1
+            else:
+                answer += 1
+                break
+        elif arr_sorted[start] + arr_sorted[end] > arr_sorted[i]:
+            end -= 1
+        else:
+            start += 1
+
+print(answer)