From d7efb7b1e36cfe94318c99f494f4e61b07767689 Mon Sep 17 00:00:00 2001
From: dwij2812 <dwijhariket@gmail.com>
Date: Fri, 25 Sep 2020 21:56:00 +0530
Subject: [PATCH] Added Breadth First Search

---
 README.md                        |  2 +-
 searching/breadthFirstSearch.go  | 72 ++++++++++++++++++++++++++++++++
 searching/interpolationSearch.go | 65 ----------------------------
 3 files changed, 73 insertions(+), 66 deletions(-)
 create mode 100644 searching/breadthFirstSearch.go
 delete mode 100644 searching/interpolationSearch.go

diff --git a/README.md b/README.md
index a2cd36b..f056ffb 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ Algorithms
   * [binary search](https://en.wikipedia.org/wiki/Binary_search_algorithm)
   * [linear search](https://en.wikipedia.org/wiki/Linear_search)
   * [jump search](https://en.wikipedia.org/wiki/Jump_search)
-  * [interpolation search](https://en.wikipedia.org/wiki/Interpolation_search)
+  * [breadth-first search](https://en.wikipedia.org/wiki/Breadth-first_search)
 
 #### Collections
 
diff --git a/searching/breadthFirstSearch.go b/searching/breadthFirstSearch.go
new file mode 100644
index 0000000..7719d3f
--- /dev/null
+++ b/searching/breadthFirstSearch.go
@@ -0,0 +1,72 @@
+package main
+
+import "fmt"
+
+func getIdx(target int, nodes []int) int {
+	for i := 0; i < len(nodes); i++ {
+		if nodes[i] == target {
+			return i
+		}
+	}
+	return -1
+}
+
+func notExist(target int, slice []int) bool {
+	for i := 0; i < len(slice); i++ {
+		if slice[i] == target {
+			return false
+		}
+	}
+	return true
+}
+
+func breadthFirstSearch(start, end int, nodes []int, edges [][]bool) bool {
+	var route []int
+	var queue []int
+	startIdx := getIdx(start, nodes)
+	queue = append(queue, startIdx)
+	for len(queue) > 0 {
+		now := queue[0]
+		route = append(route, nodes[now])
+		if len(queue) > 1 {
+			queue = queue[1:]
+		} else {
+			queue = queue[0:]
+		}
+		for i := 0; i < len(edges[now]); i++ {
+			if edges[now][i] && notExist(i, queue) {
+				queue = append(queue, i)
+			}
+			edges[now][i] = false
+			edges[i][now] = false
+		}
+		if route[len(route)-1] == end {
+			return true
+		}
+	}
+	return false
+}
+
+func main() {
+	nodes := []int{
+		1, 2, 3, 4, 5, 6,
+	}
+	/*
+		sample graph
+		①-②
+		|  |
+		③-④-⑤-⑥
+	*/
+	edges := [][]bool{
+		{false, true, true, false, false, false},
+		{true, false, false, true, false, false},
+		{true, false, false, true, false, false},
+		{false, true, true, false, true, false},
+		{false, false, false, true, false, true},
+		{false, false, false, false, true, false},
+	}
+	start := 1
+	end := 6
+	result := breadthFirstSearch(start, end, nodes, edges)
+	fmt.Println(result)
+}
diff --git a/searching/interpolationSearch.go b/searching/interpolationSearch.go
deleted file mode 100644
index 9ff4ed9..0000000
--- a/searching/interpolationSearch.go
+++ /dev/null
@@ -1,65 +0,0 @@
-package main
-
-import "fmt"
-
-func InterpolationSearch(array []int, key int) int {
-
-	min, max := array[0], array[len(array)-1]
-
-	low, high := 0, len(array)-1
-
-	for {
-		if key < min {
-			return low
-		}
-
-		if key > max {
-			return high + 1
-		}
-
-		// make a guess of the location
-		var guess int
-		if high == low {
-			guess = high
-		} else {
-			size := high - low
-			offset := int(float64(size-1) * (float64(key-min) / float64(max-min)))
-			guess = low + offset
-		}
-
-		// maybe we found it?
-		if array[guess] == key {
-			// scan backwards for start of value range
-			for guess > 0 && array[guess-1] == key {
-				guess--
-			}
-			return guess
-		}
-
-		// if we guessed to high, guess lower or vice versa
-		if array[guess] > key {
-			high = guess - 1
-			max = array[high]
-		} else {
-			low = guess + 1
-			min = array[low]
-		}
-	}
-}
-
-func main() {
-	searchValue := 0
-
-	arr := []int{1, 5, 100, 0, -100, 15, 4, 102, 30, 1000}
-	fmt.Println(arr)
-
-	var index = InterpolationSearch(arr, searchValue)
-
-	if index < 0 {
-		fmt.Println("Not found")
-		return
-	} else {
-		fmt.Println("Found at position: ", index)
-		return
-	}
-}