first commit

from old repository to a new repository

boj/11501.py

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+import sys
+input=sys.stdin.readline
+t=int(input().rstrip())
+
+for _ in range(t):
+	d=int(input().rstrip())
+	arr=list(map(int,input().rstrip().split()))
+
+	mx=0
+	s=0
+	for i in range(d):
+		a=arr.pop()
+		
+		if mx<a:
+			mx=a
+		else:
+			s+=(mx-a)
+	print(s)