lab03, Recursive and cycle functions

lab03/src/Main.java

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+public class Main {
+    public static void main(String[] args) {
+        int n = 4;
+
+        factorial fact = new factorial();
+        int res1 = fact.recursionExecute(n);
+        System.out.println("Factorial recursive n: " + n);
+        System.out.println("Factorial recursive execute: " + res1);
+
+        int res2 = fact.cycleExecute(n);
+        System.out.println("Factorial cycle n: " + n);
+        System.out.println("Factorial cycle execute: " + res2);
+        assert res1 == res2 : "different values";
+
+
+        fibonacci fib = new fibonacci();
+
+        res1 = fib.recursionExecute(n);
+        System.out.println("Fibonacci recursive n: " + n);
+        System.out.println("Fibonacci recursive execute: " + res1);
+
+        res2 = fib.cycleExecute(n);
+        System.out.println("Fibonacci cycle n: " + n);
+        System.out.println("Fibonacci cycle execute: " + res2);
+        assert res1 == res2 : "different values";
+
+
+        int number = 233151;
+        digitsSum digitSum = new digitsSum();
+        res1 = digitSum.execute(number);
+        System.out.println("Digits sum number: " + number);
+        System.out.println("Digits sum recursive execute: " + res1);
+
+        int x = 5;
+        int y = 2;
+        sum sum = new sum();
+        res1 = sum.execute(x,y);
+        System.out.println("Sum without arithmetic operations x: " + x + ", y: " + y);
+        System.out.println("Sum without arithmetic operations execute: " + res1);
+
+    }
+}

lab03/src/digitsSum.java

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+public class digitsSum {
+    int execute(int number){
+        if (number == 0){
+            return 0;
+        }
+
+        return (number % 10) + execute(number/10);
+    }
+}

lab03/src/factorial.java

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+public class factorial {
+    int recursionExecute(int n){
+        if (n < 1) return 1;
+
+        return n * recursionExecute(n - 1);
+    }
+    int cycleExecute(int n){
+        int res = 1;
+        for(int i = 1; i <= n; i++){
+            res *= i;
+        }
+
+        return res;
+    }
+}

lab03/src/fibonacci.java

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+public class fibonacci {
+
+    int recursionExecute(int n){
+        if (n <= 1) return n;
+
+        int curr = recursionExecute(n - 1);
+        int prev = recursionExecute(n - 2);
+
+        return curr + prev;
+    }
+    int cycleExecute(int n){
+        int prev = 0;
+        int curr = 1;
+        for (int i = 0; i <= n; i++){
+            int temp = curr;
+            curr = prev + curr;
+            prev = temp;
+        }
+
+        return curr;
+    }
+}

lab03/src/sum.java

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+public class sum {
+    public int execute(int x, int y){
+        if (y == 0) return x;
+
+        return execute(x ^ y, (x & y) << 1);
+    }
+}