diff --git a/syamauchi/src/C099_origami.java b/syamauchi/src/C099_origami.java
new file mode 100644
index 0000000000000000000000000000000000000000..d7a073bd802c896ba94d7c158548683093f11ad1
--- /dev/null
+++ b/syamauchi/src/C099_origami.java
@@ -0,0 +1,37 @@
+package src;
+
+import java.util.Scanner;
+
+public class C099_origami {
+  // 一辺の長さ
+  private final int length;
+
+  private C099_origami(final int length) {
+    this.length = length;
+  }
+
+  public static void main(String[] args) {
+    final Scanner sc = new Scanner(System.in);
+    // 折り紙の枚数
+    final int sheets = sc.nextInt();
+    // 一辺の長さを取得して計算
+    new C099_origami(sc.nextInt()).calc(sheets, sc);
+    sc.close();
+  }
+
+  private void calc(final int sheets, final Scanner sc) {
+    int maxLength = this.length;
+    for (int i = 1; i < sheets; i++) {
+      // 横幅の計算
+      maxLength = maxLength + overlap(sc.nextInt());
+    }
+    sc.close();
+    // 面積の計算
+    System.out.println(length * maxLength);
+  }
+
+  // 重なりの部分の計算
+  private int overlap(final int i) {
+    return this.length - i;
+  }
+}