[w4/e1] Added solution

1 files changed, 90 insertions, 0 deletions

diff --git a/week04/exercise01.cpp b/week04/exercise01.cpp
new file mode 100644
index 0000000..6b76cf6
--- /dev/null
+++ b/week04/exercise01.cpp
@@ -0,0 +1,90 @@
+#include <iostream>
+
+// Подточка а)
+
+unsigned long long tenTo(unsigned long long power) {
+	unsigned long long result = 1;
+	while (power > 0) {
+		result *= 10;
+		power--;
+	}
+	return result;
+}
+
+unsigned numLen(unsigned long long n) {
+	unsigned len = 0;
+	while (n > 0) {
+		len++;
+		n /= 10;
+	}
+	return len;
+}
+
+unsigned long long get(unsigned long long n, unsigned start, unsigned end) {
+	return (n / tenTo(numLen(n) - end)) % tenTo(end - start + 1);
+}
+
+unsigned long long remove(unsigned long long n, unsigned start, unsigned len) {
+	unsigned numDigits = numLen(n);
+	return (n / tenTo(numDigits - start + 1)) * tenTo(numDigits - start + 1 - len)
+	       + n % tenTo(numDigits - start + 1 - len);
+}
+
+unsigned long long insert(unsigned long long n, unsigned start, unsigned len, unsigned long long toInsert) {
+	unsigned numDigits = numLen(n);
+	return (n / tenTo(numDigits - start + 1)) * tenTo(numDigits - start + len + 1)
+	       + toInsert * tenTo(numDigits - start + 1)
+	       + n % tenTo(numDigits - start + 1);
+}
+
+// Подточка б)
+
+unsigned long long copy(unsigned long long n, unsigned from, unsigned len, unsigned to) {
+	return insert(n, to, len, get(n, from, from + len - 1));
+}
+
+unsigned long long cut(unsigned long long n, unsigned from, unsigned len, unsigned to) {
+	unsigned long long cutNum = get(n, from, from + len - 1);
+	return insert(remove(n, from, len), to, len, cutNum);
+}
+
+unsigned long long replace(unsigned long long n, unsigned from, unsigned len, unsigned long long replaceWith) {
+	return insert(remove(n, from, len), from, numLen(replaceWith), replaceWith);
+}
+
+unsigned long long prepend(unsigned long long n, unsigned long long prependWith) {
+	return insert(n, 1, numLen(prependWith), prependWith);
+}
+
+unsigned long long append(unsigned long long n, unsigned long long appendWith) {
+	return insert(n, numLen(n) + 1, numLen(appendWith), appendWith);
+}
+
+// Подточка в)
+
+int main() {
+	char command;
+	std::cin >> command;
+	switch (command) {
+		case 'c': unsigned long long n; unsigned from, len, to;
+		          std::cin >> n >> from >> len >> to;
+		          std::cout << copy(n, from, len, to) << std::endl;
+		          break;
+		case 'x': 
+		          std::cin >> n >> from >> len >> to;
+		          std::cout << cut(n, from, len, to) << std::endl;
+		          break;
+		case 'r': unsigned long long replaceWith;
+		          std::cin >> n >> from >> len >> replaceWith;
+		          std::cout << replace(n, from, len, replaceWith) << std::endl;
+		          break;
+		case 'p': unsigned long long prependWith;
+		          std::cin >> n >> prependWith;
+		          std::cout << prepend(n, prependWith) << std::endl;
+		          break;
+		case 'a': unsigned long long appendWith;
+		          std::cin >> n >> appendWith;
+		          std::cout << append(n, appendWith) << std::endl;
+		          break;
+	}
+}