Merge pull request #131 from YoonYn9915/main

YoonYn9915 / 1월 4주차 / 3문제

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)

YoonYn9915/sort/2025-01-25-[백준]-#18114-블랙 프라이데이.py

@@ -0,0 +1,48 @@
+from collections import deque
+
+N, C = map(int, input().split())
+
+arr = [0]
+arr = arr + list(map(int, input().split()))
+flag = 0
+
+arr.sort()
+
+
+def binary_search(start, end, diff):
+    while start <= end:
+        mid = (start + end) // 2
+        if arr[mid] == diff:
+            return 1
+        elif arr[mid] > diff:
+            end = mid - 1
+        else:
+            start = mid + 1
+    return 0
+
+
+start = 0
+end = len(arr) - 1
+
+if C in arr:
+    print(1)
+    exit(0)
+
+while start < end:
+    arr_sum = arr[start] + arr[end]
+    if arr_sum > C:
+        end -= 1
+    elif arr_sum == C:
+        flag = 1
+        break
+    elif arr_sum < C:
+        diff = C - arr_sum
+        if diff != arr[start] and diff != arr[end] and binary_search(start, end, diff) == 1:
+            flag = 1
+            break
+        start += 1
+
+if flag == 1:
+    print(1)
+else:
+    print(0)

YoonYn9915/sort/2025-01-25-[백준]-#2252-줄 세우기.py

@@ -0,0 +1,45 @@
+from collections import deque
+
+
+def topology_sort(graph, inDegree):
+    queue = deque()
+    # 위상정렬 결과를 담을 리스트
+    result = []
+
+    # 진입차수가 0인 정점을 큐에 추가
+    for num in range(len(inDegree)):
+        if inDegree[num] == 0:
+            queue.append(num + 1)
+
+    while queue:
+        now = queue.popleft()
+        result.append(now)
+
+        # 진입차수 업데이트
+        for vertex in graph[now - 1]:
+            inDegree[vertex - 1] -= 1
+            # 진입차수가 0인 정점을 큐에 추가
+            if inDegree[vertex - 1] == 0:
+                queue.append(vertex)
+
+    return result
+
+
+# 정점, 간선의 개수
+N, M = map(int, input().split())
+
+# 진입차수
+inDegree = [0] * N
+# 그래프
+graph = [[] for _ in range(N)]
+
+for i in range(M):
+    first, second = map(int, input().split())
+    # 그래프 변경
+    graph[first - 1].append(second)
+    # 진입차수 증가
+    inDegree[second - 1] += 1
+
+result = topology_sort(graph, inDegree)
+for ans in result:
+    print(ans, end=" ")