add can make arithmetic progression

Author: boudhayan

Algorithm Solutions In Swift.xcodeproj/project.pbxproj

@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		1F21EEE72F54613100E0274E /* MakeArithmeticProgression.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1F21EEE62F54612300E0274E /* MakeArithmeticProgression.swift */; };
 		1F7037522F3E5618002CFFE1 /* Algorithms in Frameworks */ = {isa = PBXBuildFile; productRef = 1F7037512F3E5618002CFFE1 /* Algorithms */; };
 		1F7037552F3E5642002CFFE1 /* BasicContainers in Frameworks */ = {isa = PBXBuildFile; productRef = 1F7037542F3E5642002CFFE1 /* BasicContainers */; };
 		1F7037572F3E5642002CFFE1 /* BitCollections in Frameworks */ = {isa = PBXBuildFile; productRef = 1F7037562F3E5642002CFFE1 /* BitCollections */; };
@@ -332,6 +333,7 @@
 /* End PBXCopyFilesBuildPhase section */
 
 /* Begin PBXFileReference section */
+		1F21EEE62F54612300E0274E /* MakeArithmeticProgression.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MakeArithmeticProgression.swift; sourceTree = "<group>"; };
 		1F85E42D2F500D060097933E /* RecursiveBubbleSort.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RecursiveBubbleSort.swift; sourceTree = "<group>"; };
 		1F85E4302F500D210097933E /* RecusriveInsertionSort.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RecusriveInsertionSort.swift; sourceTree = "<group>"; };
 		1F85E4352F5062420097933E /* SortedRotated.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SortedRotated.swift; sourceTree = "<group>"; };
@@ -598,6 +600,14 @@
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
+		1F21EEE52F54611E00E0274E /* Can Make Arithmetic Progression */ = {
+			isa = PBXGroup;
+			children = (
+				1F21EEE62F54612300E0274E /* MakeArithmeticProgression.swift */,
+			);
+			path = "Can Make Arithmetic Progression";
+			sourceTree = "<group>";
+		};
 		1F85E42C2F500D010097933E /* Recursive Bubble Sort */ = {
 			isa = PBXGroup;
 			children = (
@@ -1350,6 +1360,7 @@
 				6A88CEEA26C3132700A3746B /* Merge Intervals */,
 				6A88CEE626C056BD00A3746B /* 3 Sum Closest */,
 				1F85E42F2F500D1D0097933E /* Recursive Insertion Sort */,
+				1F21EEE52F54611E00E0274E /* Can Make Arithmetic Progression */,
 			);
 			path = LeetCode;
 			sourceTree = "<group>";
@@ -2993,6 +3004,7 @@
 				6A651A4C2907866D000731BB /* FirstUniqueCharacter.swift in Sources */,
 				6AF5788626A2E67F007B37CA /* TwoNumberSum.swift in Sources */,
 				6AF5790926A6E0FC007B37CA /* BinarySearchTrees.swift in Sources */,
+				1F21EEE72F54613100E0274E /* MakeArithmeticProgression.swift in Sources */,
 				6AF578BC26A34C97007B37CA /* RemoveDuplicatesFromLinkedList.swift in Sources */,
 				6AF5795A26AC287A007B37CA /* ThreeNumberSort.swift in Sources */,
 				6A502306285C8C4600688107 /* ReconstructBST.swift in Sources */,

Algorithm Solutions In Swift/main.swift

@@ -2,42 +2,5 @@ import Foundation
 
 
 
-func spiralOrder1(_ matrix: [[Int]]) -> [Int] {
-    var startRow = 0
-    var endRow = matrix.count - 1
-
-    var startCol = 0
-    var endCol = matrix[0].count - 1
-
-    var traversed = [Int]()
-
-    while startRow <= endRow, startCol <= endCol {
-        for col in stride(from: startCol, through: endCol, by: 1) {
-            traversed.append(matrix[startRow][col])
-        }
-
-        if startRow == endRow { break }
-
-        for row in stride(from: startRow + 1, through: endRow, by: 1) {
-            traversed.append(matrix[row][endCol])
-        }
-
-        if startCol == endCol { break }
-        for col in stride(from: endCol - 1, through: startCol, by: -1) {
-            traversed.append(matrix[endRow][col])
-        }
-
-        for row in stride(from: endRow - 1, through: startRow + 1, by: -1) {
-            traversed.append(matrix[row][startCol])
-        }
-
-        startRow += 1
-        endRow -= 1
-
-        startCol += 1
-        endCol -= 1
-    }
-    return traversed
-}
-var array = [[1, 2, 3]]/*[[1,2,3,4],[5,6,7,8],[9,10,11,12]]*/
-print(spiralOrder1(array))
+var array = [3, 5, 7]
+print(canMakeArithmeticProgression(array))

LeetCode/Can Make Arithmetic Progression/MakeArithmeticProgression.swift

@@ -0,0 +1,24 @@
+//
+//  MakeArithmeticProgression.swift
+//  Algorithm Solutions In Swift
+//
+//  Created by littlebanana on 01/03/26.
+//
+
+func canMakeArithmeticProgression(_ arr: [Int]) -> Bool {
+    // In a valid AP, d = (max - min) / (n - 1) where n is the total number of elements in AP
+    let min = arr.min()!, max = arr.max()!
+    // if max - min is zero, then all the elements are same, so return true
+    if max - min == 0 { return true }
+    // if there is a remainder in (max - min) % (n - 1), means AP can't be created as diff will be in fraction
+    if (max - min)%(arr.count - 1) != 0 { return false }
+    let diff = (max - min) / (arr.count - 1)
+    // create set and using diff check if all the elements exist
+    let hashSet = Set(arr)
+    for i in 0..<arr.count {
+        if !hashSet.contains(min + i * diff) {
+            return false
+        }
+    }
+    return true
+}