diff --git a/graph/lca.cpp b/graph/lca.cpp
index 77b874c8a7a04701ad82bf75028e39ccef8fe3a0..5f43a335801c694e24bfac6e4083c6cfaa5fe8a4 100644
--- a/graph/lca.cpp
+++ b/graph/lca.cpp
@@ -11,6 +11,8 @@
  *      *** = used in both * and **
  */
 
+#define MAXLOG 20 //log2(MAX)
+
 vector<int> graph[MAX]; //*** vector<ii>
 
 int h[MAX];
diff --git a/graph/tarjan.cpp b/graph/tarjan.cpp
index f9e1952d18a339abf6c5abe9bdb6fa21c284a162..bfcccdcac2ccf30df283f0b9d936972b799a1394 100644
--- a/graph/tarjan.cpp
+++ b/graph/tarjan.cpp
@@ -13,7 +13,7 @@ int ncomp, ind;
 int cont[MAX], parent[MAX];
 int low[MAX], L[MAX];
 
-// Fills scc with strongly connected components of graph
+// Fills SCC with strongly connected components of graph
 void dfs(int x) {
   L[x] = ind;
   low[x] = ind++;
diff --git a/graph/topological_sort.cpp b/graph/topological_sort.cpp
index d5b673967e2898d76a5ed9b2694a1b49decc6fd2..b4a7169849cba869d85205824f790ccad91e694a 100644
--- a/graph/topological_sort.cpp
+++ b/graph/topological_sort.cpp
@@ -28,7 +28,7 @@ bool dfs(int x) {
 }
 
 
-// Returns if graph contains cycle or not, and fills tsort vector with
+// Returns whether graph contains cycle or not, and fills tsort vector with
 // topological sort of the graph
 bool topological_sort(int n, vector<int> &tsort) {
   mset(cont, 0);
diff --git a/math/modular_multiplicative_inverse.cpp b/math/modular_multiplicative_inverse.cpp
index ad965244f58f4fa7c86d3f302cf00fdf13e53f54..8a0579850ed78c5de80851fcdfac9877695af39e 100644
--- a/math/modular_multiplicative_inverse.cpp
+++ b/math/modular_multiplicative_inverse.cpp
@@ -6,7 +6,7 @@
  */
 
 // ========== Fermat's Little Theorem ==========
-// Used if m is prime
+// Used when m is prime
 
 ll power(ll x, ll y) {
   ll ans = 1;
@@ -31,7 +31,7 @@ ll mod_inverse(ll a) {
 
 
 // ========== Extended Euclidean Algorithm ==========
-// Used if m and a are coprime
+// Used when m and a are coprime
 
 // return gcd(a, b) and find x, y where:
 // a*x + b*y = gcd(a, b)
diff --git a/paradigm/kadane.cpp b/paradigm/kadane.cpp
index 8ad7c719b27f5370dd75c30218a753f716c5c09b..46d5b4ee37675be3e46a340b02e76a5062d26d54 100644
--- a/paradigm/kadane.cpp
+++ b/paradigm/kadane.cpp
@@ -1,5 +1,5 @@
 /**
- * Kadane
+ * Kadane - Largest Sum Contiguous Subarray
  *
  * Complexity (Time): O(n + m)
  * Complexity (Space): O(n + m)
@@ -8,6 +8,7 @@
 int v[MAX];
 
 int kadane() {
+
   // Maximum so far (msf), Maximum ending here (meh).
   int msf = -0x3f3f3f3f, meh = 0;
   int start = 0, end = 0, s = 0;
@@ -15,12 +16,16 @@ int kadane() {
   for (int i = 0; i < n; ++i) {
     meh += v[i];
 
+    // Store maximum so far as well as starting and ending position
+    // of the subsequence
     if (msf < meh) {
       msf = meh;
       start = s;
       end = i;
     }
 
+    // If maximum ending here is negative, then it's definitely 
+    // better to restart
     if (meh < 0) {
       meh = 0;
       s = i + 1;
diff --git a/string/kmp.cpp b/string/kmp.cpp
index 81fe7bd0a59f8a7f81147d3e1aba041c8a985e82..741289a15a306cf0a43ca35e53664eccd7d79af3 100644
--- a/string/kmp.cpp
+++ b/string/kmp.cpp
@@ -1,5 +1,5 @@
 /**
- * Knuth-Morris-Pratt - KMP
+ * Knuth-Morris-Pratt (KMP)
  *
  * Complexity (Time): 
  *   preprocess -> O(m)
diff --git a/structure/bit.cpp b/structure/bit.cpp
index e42f30525b1c3462135c410fe160ac75e71e73fd..69d3ab1815ba8b14ddd88717ce4c2ec7cd2b407d 100644
--- a/structure/bit.cpp
+++ b/structure/bit.cpp
@@ -1,5 +1,5 @@
 /**
- * Binary Indexed Tree - BIT 
+ * Binary Indexed Tree (BIT)
  *
  * Complexity (Time):
  *   Update -> O(log n)
diff --git a/structure/bit2d.cpp b/structure/bit2d.cpp
index 63f34601066b506963e33d5cd7699d973ce03bab..786faaa2c08f40241d514ee673a0822568d1221b 100644
--- a/structure/bit2d.cpp
+++ b/structure/bit2d.cpp
@@ -1,5 +1,5 @@
 /** 
- * Binary Indexed Tree 2D - BIT2D
+ * Binary Indexed Tree 2D (BIT2D)
  *
  * Complexity (Time):
  *   Update -> O(log^2 n)
diff --git a/structure/disjoint_set.cpp b/structure/disjoint_set.cpp
index 22081e04a18b63e061fb073403fcb50dcfb282ed..e8ebabe6c160f439c622e5e71d2dbe564c0c9843 100644
--- a/structure/disjoint_set.cpp
+++ b/structure/disjoint_set.cpp
@@ -10,13 +10,13 @@
 
 int par[MAX];
 int h[MAX];
-int sz[MAX];
+int size[MAX];
 
 // Initialize element x
 void make_set(int x) {
   par[x] = x;
   h[x] = 0;
-  sz[x] = 1;
+  size[x] = 1;
 }
 
 
@@ -39,13 +39,12 @@ void union_set(int x, int y) {
 
   if (h[xroot] < h[yroot]) {
     par[xroot] = yroot;
-    sz[yroot] += sz[xroot];
-  } else if (h[xroot] > h[yroot]) {
-    par[yroot] = xroot;
-    sz[xroot] += sz[yroot];
+    size[yroot] += size[xroot];
   } else {
     par[yroot] = xroot;
-    sz[xroot] += sz[yroot];
-    h[xroot]++;
+    size[xroot] += size[yroot];
+
+    if (h[xroot] == h[yroot])
+      h[xroot]++;
   }
 }
diff --git a/structure/policy_tree.cpp b/structure/policy_tree.cpp
index d93aca40959759050e131f8712062bf2d29d4a18..ee6cff39aaeb7514fbdeb8fe43db0bb6fa81ebaf 100644
--- a/structure/policy_tree.cpp
+++ b/structure/policy_tree.cpp
@@ -1,6 +1,8 @@
 /**
  * Policy Tree
  *
+ * A set-like STL structure with order statistics
+ *
  * Complexity (Time):
  *   insert        -> O(log n)
  *   erase         -> O(log n)