Update KMP.cpp

Author: Ashishgup1

KMP.cpp

@@ -2,13 +2,13 @@
 
 vector<int> prefix_function(string &s) 
 {
-	int n = (int)s.length();
+	int n = s.size();
 	vector<int> pi(n);
-	for (int i = 1; i < n; i++) 
+	for(int i = 1; i < n; i++) 
 	{
-		int j = pi[i-1];
-		while (j > 0 && s[i] != s[j])
-			j = pi[j-1];
+		int j = pi[i - 1];
+		while(j > 0 && s[i] != s[j])
+			j = pi[j - 1];
 		if (s[i] == s[j])
 			j++;
 		pi[i] = j;
@@ -18,14 +18,14 @@ vector<int> prefix_function(string &s)
 
 vector<int> find_occurences(string &text, string &pattern)
 {
-	string cur=pattern + '#' + text;
-	int sz1=text.size(), sz2=pattern.size();
+	string cur = pattern + '#' + text;
+	int sz1 = text.size(), sz2 = pattern.size();
 	vector<int> v;
-	vector<int> lps=prefix_function(cur);
-	for(int i=sz2+1;i<=sz1+sz2;i++)
+	vector<int> lps = prefix_function(cur);
+	for(int i = sz2 + 1; i <= sz1 + sz2; i++)
 	{
-		if(lps[i]==sz2)
-			v.push_back(i-2*sz2);
+		if(lps[i] == sz2)
+			v.push_back(i - 2 * sz2);
 	}
 	return v;
 }
@@ -34,14 +34,14 @@ vector<int> find_occurences(string &text, string &pattern)
 
 vector<int> prefix_function(vector<int> &v) 
 {
-	int n = (int)v.size();
+	int n = v.size();
 	vector<int> pi(n);
-	for (int i = 1; i < n; i++) 
+	for(int i = 1; i < n; i++) 
 	{
-		int j = pi[i-1];
-		while (j > 0 && v[i] != v[j])
-			j = pi[j-1];
-		if (v[i] == v[j])
+		int j = pi[i - 1];
+		while(j > 0 && v[i] != v[j])
+			j = pi[j - 1];
+		if(v[i] == v[j])
 			j++;
 		pi[i] = j;
 	}
@@ -50,26 +50,27 @@ vector<int> prefix_function(vector<int> &v)
 
 vector<int> find_occurences(vector<int> &text, vector<int> &pattern)
 {
-	vector<int> v=pattern;
+	vector<int> v = pattern;
 	v.push_back(-1);
 	for(auto &it:text)
 		v.push_back(it);
-	int sz1=text.size(), sz2=pattern.size();
-	vector<int> lps=prefix_function(v);
+	int sz1 = text.size(), sz2 = pattern.size();
+	vector<int> lps = prefix_function(v);
 	vector<int> store;
-	for(int i=sz2+1;i<=sz1+sz2;i++)
+	for(int i = sz2 + 1; i <= sz1 + sz2; i++)
 	{
-		if(lps[i]==sz2)
-			store.push_back(i-sz*2);
+		if(lps[i] == sz2)
+			store.push_back(i - 2 * sz2);
 	}
 	return v;
 }
 
-
 //Problem 1 (Basic KMP): https://codeforces.com/contest/1016/problem/B
 //Solution 1: https://codeforces.com/contest/1016/submission/41167402
 
 //Problem 2 and Solution (Cyclic Matching - Vectors): http://codeforces.com/gym/100502/submission/41562571
 
 //Problem 3 (Ranking Pattern): https://qr.ae/TUG5h9 
 //Solution 3: http://p.ip.fi/Hwpy
+
+//Problem 4: (Period of String) https://www.spoj.com/problems/FINDSR/