Merge pull request #230 from Mcbencrafter/main

Added math and bit manipulation snippets for java

Author: Mathys-Gasnier

snippets/java/bit-manipulation/bit-counting.md

@@ -0,0 +1,23 @@
+---
+title: Bit Counting
+description: Counts the set bits in the binary representation of an integer
+author: Mcbencrafter
+tags: math,number,bits,bit-counting
+---
+
+```java
+public static int countBits(int number) {
+    int bits = 0;
+        
+    while (number > 0) {
+        bits += number & 1;
+        number >>= 1;
+    }
+
+    return bits;
+}
+
+// Usage:
+int number = 5;
+System.out.println(countBits(5)); // 2 (101)
+```

snippets/java/bit-manipulation/is-power-of-two.md

@@ -0,0 +1,16 @@
+---
+title: Is Power Of Two
+description: Checks if a number is a power of two
+author: Mcbencrafter
+tags: math,number,bit,power-of-two
+---
+
+```java
+public static boolean isPowerOfTwo(int number) {
+    return (number > 0) && ((number & (number - 1)) == 0);
+}
+
+// Usage:
+int number = 16;
+System.out.println(isPowerOfTwo(5)); // true (2^4)
+```

snippets/java/date-time/date-time-formatting-american.md

@@ -1,5 +1,5 @@
 ---
-title: Date time formatting american
+title: Date Time Formatting American
 description: Formats a timestamp to a human-readable date-time string in the format "MM/dd/yyyy hh:mm:ss a"
 author: Mcbencrafter
 tags: date,time,date-time,formatting,american

snippets/java/date-time/date-time-formatting-european.md

@@ -1,5 +1,5 @@
 ---
-title: Date time formatting european
+title: Date Time Formatting European
 description: Formats a timestamp to a human-readable date-time string in the format "dd.MM.yyyy HH:mm:ss"
 author: Mcbencrafter
 tags: date,time,date-time,formatting,european

snippets/java/date-time/duration-formatting-hours-minutes-seconds.md

@@ -1,5 +1,5 @@
 ---
-title: Duration formatting hours minutes seconds
+title: Duration Formatting Hours Minutes Seconds
 description: Converts a given time duration to a human-readable string in the format "hh:mm(:ss)"
 author: Mcbencrafter
 tags: time,formatting,hours,minutes,seconds

snippets/java/date-time/duration-formatting-minutes-seconds.md

@@ -1,5 +1,5 @@
 ---
-title: Duration formatting minutes seconds
+title: Duration Formatting Minutes Seconds
 description: Converts a given time duration to a human-readable string in the format "mm:ss"
 author: Mcbencrafter
 tags: time,formatting,minutes,seconds

snippets/java/math/checksum.md

@@ -0,0 +1,24 @@
+---
+title: Checksum
+description: Calculates the checksum of an int
+author: Mcbencrafter
+tags: math,number,checksum
+---
+
+```java
+public static int checksum(int number) {
+    number = Math.abs(number);
+    int sum = 0;
+
+    while (number != 0) {
+        sum += number % 10;
+        number /= 10;
+    }
+
+    return sum;
+}
+
+// Usage:
+int number = 12345;
+System.out.println(checksum(number)); // 15 = 1+2+3+4+5
+```

snippets/java/math/factorial.md

@@ -0,0 +1,24 @@
+---
+title: Factorial
+description: Computes the factorial of a given number
+author: Mcbencrafter
+tags: math,number,factorial
+---
+
+```java
+import java.math.BigInteger;
+
+public static BigInteger factorial(int number) {
+    BigInteger result = BigInteger.ONE;
+
+    for (int currentNumber = 1; currentNumber <= number; currentNumber++) {
+        result = result.multiply(BigInteger.valueOf(currentNumber));
+    }
+
+    return result;
+}
+
+// Usage:
+int number = 6;
+System.out.println(factorial(number)); // 720 = 6*5*4*3*2
+```

snippets/java/math/fibonacci.md

@@ -0,0 +1,19 @@
+---
+title: Fibonacci
+description: Calculates the nth fibonacci number
+author: Mcbencrafter
+tags: math,number,fibonacci
+---
+
+```java
+public static int fibonacci(int number) {
+    if (number <= 1) 
+        return number;
+        
+    return fibonacci(number - 1) + fibonacci(number - 2);
+}
+
+// Usage:
+int number = 5;
+System.out.println(fibonacci(number)) // 3 (0, 1, 1, 2, 3)
+```

snippets/java/math/greatest-common-divisor.md

@@ -0,0 +1,23 @@
+---
+title: Greatest Common Divisor
+description: Calculates the greatest common divisor (gcd) of two numbers
+author: Mcbencrafter
+tags: math,number,greatest-common-devisor,gcd,euclidean-algorithm
+---
+
+```java
+public static int gcd(int number1, int number2) {
+    while (number2 != 0) {
+        int remainder = number2;
+        number2 = number1 % number2;
+        number1 = remainder;
+    }
+
+    return number1;
+}
+
+// Usage:
+int a = 16;
+int b = 12;
+System.out.println(gcd(a, b)); // 4
+```