From fb8dafe58221235d7001e3e6e46afdd844e060c7 Mon Sep 17 00:00:00 2001
From: Viktor Patchev <viktor.patchev@inplayer.com>
Date: Mon, 2 Mar 2020 11:37:54 +0100
Subject: [PATCH] Book-store solution GO track exercism

---
 viktor/book-store/bookstore.go | 99 ++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)
 create mode 100644 viktor/book-store/bookstore.go

diff --git a/viktor/book-store/bookstore.go b/viktor/book-store/bookstore.go
new file mode 100644
index 0000000..102db4b
--- /dev/null
+++ b/viktor/book-store/bookstore.go
@@ -0,0 +1,99 @@
+package bookstore
+
+func Cost(books []int) int {
+	var one, two, three, four, five float64
+	var popust int
+	var total float64
+	var totalBooks []float64
+	var min float64
+	for _, value := range books {
+		if value == 1 {
+			one++
+		} else if value == 2 {
+			two++
+		} else if value == 3 {
+			three++
+		} else if value == 4 {
+			four++
+		} else if value == 5 {
+			five++
+		}
+	}
+	for one > 0 || two > 0 || three > 0 || four > 0 || five > 0 {
+		popust = 0
+
+		if one > 0 {
+			popust++
+		}
+		one--
+
+		if two > 0 {
+			popust++
+		}
+		two--
+
+		if three > 0 {
+			popust++
+		}
+		three--
+
+		if four > 0 {
+			popust++
+		}
+		four--
+
+		if five > 0 {
+			popust++
+		}
+		five--
+
+		if popust == 1 {
+			total += 800
+		}
+		if popust == 2 {
+			total += 2 * 800 * 0.95
+		}
+		if popust == 3 {
+			total += 3 * 800 * 0.9
+		}
+		if popust == 4 {
+			total += 4 * 800 * 0.8
+		}
+		if popust == 5 {
+			if one == two && two == three && (one+two+three)/3 < (four+five)/2 ||
+				one == two && two == four && (one+two+four)/3 < (three+five)/2 ||
+				one == two && two == five && (one+two+five)/3 < (three+four)/2 ||
+				two == three && three == four && (one+three+four)/3 < (two+five)/2 ||
+				two == three && three == five && (two+three+five)/3 < (one+four)/2 ||
+				three == four && four == five && (three+four+five)/3 < (one+two)/2 {
+				total += 5 * 800 * 0.75
+				continue
+			}
+
+			if one != two || one != three || one != four || one != five {
+				total += 4 * 800 * 0.8
+				min = one
+				totalBooks = append(totalBooks, one, two, three, four, five)
+				for _, value := range totalBooks {
+					if value < min {
+						min = value
+					}
+				}
+				if one == min {
+					one++
+				} else if two == min {
+					two++
+				} else if three == min {
+					three++
+				} else if four == min {
+					four++
+				} else if five == min {
+					five++
+				}
+			} else {
+				total += 5 * 800 * 0.75
+			}
+		}
+	}
+	return int(total)
+}