diff --git a/src/main/java/io/github/spannm/leetcode/lc1/lc1200/Problem1244.java b/src/main/java/io/github/spannm/leetcode/lc1/lc1200/Problem1244.java
index 632f0732..37a38804 100644
--- a/src/main/java/io/github/spannm/leetcode/lc1/lc1200/Problem1244.java
+++ b/src/main/java/io/github/spannm/leetcode/lc1/lc1200/Problem1244.java
@@ -9,8 +9,8 @@
 class Problem1244 extends LeetcodeProblem {
 
     static class Leaderboard {
-        private final Map<Integer, Integer>     d    = new HashMap<>();
-        private final TreeMap<Integer, Integer> rank = new TreeMap<>((a, b) -> b - a);
+        private final Map<Integer, Integer> d    = new HashMap<>();
+        private final Map<Integer, Integer> rank = new TreeMap<>((a, b) -> b - a);
 
         Leaderboard() {
         }
diff --git a/src/main/java/io/github/spannm/leetcode/lc1/lc1500/Problem1500.java b/src/main/java/io/github/spannm/leetcode/lc1/lc1500/Problem1500.java
index 7ce09b6d..42bcad4f 100644
--- a/src/main/java/io/github/spannm/leetcode/lc1/lc1500/Problem1500.java
+++ b/src/main/java/io/github/spannm/leetcode/lc1/lc1500/Problem1500.java
@@ -7,10 +7,10 @@
 class Problem1500 extends LeetcodeProblem {
 
     static class FileSharing {
-        private final int                            chunks;
-        private int                                  cur;
-        private final TreeSet<Integer>               reused;
-        private final TreeMap<Integer, Set<Integer>> userChunks;
+        private final int                        chunks;
+        private int                              cur;
+        private final TreeSet<Integer>           reused;
+        private final Map<Integer, Set<Integer>> userChunks;
 
         FileSharing(int _m) {
             chunks = _m;
diff --git a/src/main/java/io/github/spannm/leetcode/lc1/lc1600/Problem1656.java b/src/main/java/io/github/spannm/leetcode/lc1/lc1600/Problem1656.java
index 1b5ca150..6b6a2a79 100644
--- a/src/main/java/io/github/spannm/leetcode/lc1/lc1600/Problem1656.java
+++ b/src/main/java/io/github/spannm/leetcode/lc1/lc1600/Problem1656.java
@@ -4,14 +4,15 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.TreeMap;
 
 class Problem1656 extends LeetcodeProblem {
 
     static class OrderedStream {
-        private final TreeMap<Integer, String> map;
-        private int                            ptr;
-        private final int                      limit;
+        private final Map<Integer, String> map;
+        private int                        ptr;
+        private final int                  limit;
 
         OrderedStream(int _n) {
             map = new TreeMap<>();
diff --git a/src/main/java/io/github/spannm/leetcode/lc2/lc2500/Problem2502.java b/src/main/java/io/github/spannm/leetcode/lc2/lc2500/Problem2502.java
index 96213dc7..62eed366 100644
--- a/src/main/java/io/github/spannm/leetcode/lc2/lc2500/Problem2502.java
+++ b/src/main/java/io/github/spannm/leetcode/lc2/lc2500/Problem2502.java
@@ -7,7 +7,7 @@
 class Problem2502 extends LeetcodeProblem {
 
     static class Allocator {
-        private final TreeMap<Integer, Integer>   tm = new TreeMap<>();
+        private final Map<Integer, Integer>       tm = new TreeMap<>();
         private final Map<Integer, List<Integer>> d  = new HashMap<>();
 
         Allocator(int n) {