Merge pull request #167 from AlgoLeadMe/47-tgyuuAn

47-tgyuuAn

tgyuuAn/README.md

@@ -48,4 +48,5 @@
 | 44차시 | 2023.03.13 |  트라이  | <a href="https://www.acmicpc.net/problem/14725">개미굴</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/159
 | 45차시 | 2023.03.16 |  트라이  | <a href="https://www.acmicpc.net/problem/31413">트라이</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/162
 | 46차시 | 2023.03.20 |  트라이  | <a href="https://www.acmicpc.net/problem/27652">AB</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/165
+| 47차시 | 2023.03.22 |  수학, 분할정복  | <a href="https://www.acmicpc.net/problem/15824">너 봄에는 캡사이신이 맛있단다</a> | https://github.com/AlgoLeadMe/AlgoLeadMe-1/pull/167
 ---

tgyuuAn/수학/너 봄에는 캡사이신이 맛있단다.py

@@ -0,0 +1,33 @@
+import sys
+
+DIV = 1_000_000_007
+
+def input(): return sys.stdin.readline().rstrip()
+
+def power(n, over):
+    if over == 0: return 1
+    elif over == 1: return n
+    elif over %2 == 0: 
+        half = (power(n, over//2) % DIV)
+        return (half * half) % DIV
+    else: 
+        half = (power(n, over//2) % DIV)
+        return (half * half * (n % DIV)) % DIV
+
+N = int(input())
+numbers = sorted(list(map(int,input().split())))
+DP = [-1 for _ in range(N)]
+answer = 0
+
+for start_idx in range(N):
+    start_num = numbers[start_idx]
+    end_num = numbers[N-start_idx-1]
+
+    # 만약 캐싱이 되어있지 않을 경우 직접 계산
+    if DP[N-start_idx-1] == -1: DP[N-start_idx-1] = power(2, N-start_idx-1)
+
+    # 한번이라도 계산  했으면 바로 이용
+    answer += ((end_num % DIV) * (DP[N-start_idx-1] % DIV)) % DIV
+    answer -= ((start_num % DIV) * (DP[N-start_idx-1] % DIV)) % DIV
+
+print(answer % DIV)