From 778250ab66c6d27bb81d26d650e1ed65d6f75c1a Mon Sep 17 00:00:00 2001
From: Ren Baoshuo <i@baoshuo.ren>
Date: Mon, 21 Sep 2020 19:15:08 +0800
Subject: [PATCH] =?UTF-8?q?P5534=20=E3=80=90XR-3=E3=80=91=E7=AD=89?=
 =?UTF-8?q?=E5=B7=AE=E6=95=B0=E5=88=97?=
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R38704401
---
 problem/P5534/P5534.cpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 problem/P5534/P5534.cpp

diff --git a/problem/P5534/P5534.cpp b/problem/P5534/P5534.cpp
new file mode 100644
index 00000000..68d71015
--- /dev/null
+++ b/problem/P5534/P5534.cpp
@@ -0,0 +1,12 @@
+// R38704401
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main() {
+    long long a[2], n;
+    scanf("%lld%lld%lld", &a[0], &a[1], &n);
+    cout << n * a[0] + n * (n - 1) * (a[1] - a[0]) / 2 << endl;
+    return 0;
+}