Initial commit

2019/republic/12_d1/anagrame.cpp

@@ -0,0 +1,61 @@
+#include <iostream>
+#include <fstream>
+#include <unordered_map>
+
+using namespace std;
+
+ifstream input_stream;
+ofstream output_stream;
+
+
+int findAnagramPos(string content, string title) {
+	const uint32_t CONTENT_LEN = content.length();
+	const uint32_t TITLE_LEN = title.length();
+
+	unordered_map<char, uint32_t> target, anagram;
+	for (uint32_t i = 0; i < TITLE_LEN; i++) {
+		target[title[i]]++;
+		anagram[content[i]]++;
+	}
+
+	if (target == anagram) {
+		return 0;
+	}
+
+	for (uint32_t i = TITLE_LEN; i < CONTENT_LEN; i++) {
+		/**
+		Old first character pos = i - TITLE_LEN
+		New first character pos = i - TITLE_LEN + 1
+		Old last character pos = i - 1
+		New last character pos = i
+		*/
+		char firstChar = content[i - TITLE_LEN];
+		anagram[firstChar]--;
+
+		if (anagram[firstChar] == 0) {
+			anagram.erase(firstChar);
+		}
+
+		anagram[content[i]]++;
+
+		if (target == anagram) {
+			return i - TITLE_LEN;
+		}
+	}
+
+	return -1;
+}
+
+
+int main() {
+	input_stream.open("input.txt");
+
+	string content, title;
+	input_stream >> content;
+	input_stream >> title;
+
+	cout << findAnagramPos(content, title) << endl;	
+
+	input_stream.close();
+	return 0;
+}