اکنون در دسترس! پژوهش تلگرام ۲۰۲۵ — مهمترین بینشهای سال 
Tech Jargon - Decoded
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نمایش بیشتر2 015
مشترکین
-124 ساعت
-57 روز
-4030 روز
آرشیو پست ها
Reverse a String (Iterative & Recursive)
public class StringReversal {
public static String reverseIterative(String str) {
StringBuilder reversed = new StringBuilder();
for (int i = str.length() - 1; i >= 0; i--) {
reversed.append(str.charAt(i));
}
return reversed.toString();
}
public static String reverseRecursive(String str) {
if (str.isEmpty()) {
return str;
} else {
return reverseRecursive(str.substring(1)) + str.charAt(0);
}
}
public static void main(String[] args) {
String input = "hello";
String reversedIterative = reverseIterative(input);
String reversedRecursive = reverseRecursive(input);
System.out.println("Iterative: " + reversedIterative);
System.out.println("Recursive: " + reversedRecursive);
}
}Count Primes Less than N
public class CountPrimes {
public int countPrimes(int n) {
if (n <= 2) {
return 0;
}
boolean[] isPrime = new boolean[n];
for (int i = 2; i < n; i++) {
isPrime[i] = true;
}
for (int i = 2; i * i < n; i++) {
if (!isPrime[i]) {
continue;
}
for (int j = i * i; j < n; j += i) {
isPrime[j] = false;
}
}
int count = 0;
for (int i = 2; i < n; i++) {
if (isPrime[i]) {
count++;
}
}
return count;
}
public static void main(String[] args) {
CountPrimes cp = new CountPrimes();
int n = 10;
int primeCount = cp.countPrimes(n);
System.out.println("Number of primes less than " + n + " is: " + primeCount);
}
}Count Primes Less than N
public class CountPrimes {
public int countPrimes(int n) {
if (n <= 2) return 0;
boolean[] isPrime = new boolean[n];
for (int i = 2; i < n; i++) {
isPrime[i] = true;
}
for (int i = 2; i * i < n; i++) {
if (!isPrime[i]) continue;
for (int j = i * i; j < n; j += i) {
isPrime[j] = false;
}
}
int count = 0;
for (int i = 2; i < n; i++) {
if (isPrime[i]) count++;
}
return count;
}
public static void main(String[] args) {
CountPrimes cp = new CountPrimes();
int n = 10;
int result = cp.countPrimes(n);
System.out.println("Number of primes less than " + n + " is: " + result);
}
}Fast Fibonacci using Matrix Exponentiation
public class Fibonacci {
public static long fibonacci(int n) {
if (n <= 1) {
return n;
}
long[][] baseMatrix = {{1, 1}, {1, 0}};
long[][] resultMatrix = matrixPower(baseMatrix, n - 1);
return resultMatrix[0][0];
}
private static long[][] matrixMultiply(long[][] a, long[][] b) {
long[][] result = new long[2][2];
result[0][0] = a[0][0] * b[0][0] + a[0][1] * b[1][0];
result[0][1] = a[0][0] * b[0][1] + a[0][1] * b[1][1];
result[1][0] = a[1][0] * b[0][0] + a[1][1] * b[1][0];
result[1][1] = a[1][0] * b[0][1] + a[1][1] * b[1][1];
return result;
}
private static long[][] matrixPower(long[][] base, int n) {
long[][] result = {{1, 0}, {0, 1}};
long[][] temp = base;
while (n > 0) {
if ((n & 1) == 1) {
result = matrixMultiply(result, temp);
}
temp = matrixMultiply(temp, temp);
n >>= 1;
}
return result;
}
public static void main(String[] args) {
int n = 10;
System.out.println("Fibonacci(" + n + ") = " + fibonacci(n));
}
}Count Primes Less than N
public class CountPrimes {
public int countPrimes(int n) {
if (n <= 2) {
return 0;
}
boolean[] isPrime = new boolean[n];
for (int i = 2; i < n; i++) {
isPrime[i] = true;
}
for (int i = 2; i * i < n; i++) {
if (!isPrime[i]) continue;
for (int j = i * i; j < n; j += i) {\n isPrime[j] = false;
}
}
int count = 0;
for (int i = 2; i < n; i++) {
if (isPrime[i]) count++;
}
return count;
}
public static void main(String[] args) {
CountPrimes cp = new CountPrimes();
int n = 10;
int primeCount = cp.countPrimes(n);
System.out.println("Number of primes less than " + n + " is: " + primeCount);
}
}Fast Fibonacci using Matrix Exponentiation
public class Fibonacci { public static long fibonacci(int n) { if (n <= 1) return n; long[][] matrix = {{1, 1}, {1, 0}}; power(matrix, n - 1); return matrix[0][0]; } private static void power(long[][] matrix, int n) { if (n == 0 || n == 1) return; long[][] temp = {{1, 1}, {1, 0}}; power(matrix, n / 2); multiply(matrix, matrix); if (n % 2 != 0) multiply(matrix, temp); } private static void multiply(long[][] a, long[][] b) { long a00 = a[0][0], a01 = a[0][1], a10 = a[1][0], a11 = a[1][1]; long b00 = b[0][0], b01 = b[0][1], b10 = b[1][0], b11 = b[1][1]; a[0][0] = (a00 * b00 + a01 * b10); a[0][1] = (a00 * b01 + a01 * b11); a[1][0] = (a10 * b00 + a11 * b10); a[1][1] = (a10 * b01 + a11 * b11); } public static void main(String[] args) { int n = 10; System.out.println("Fibonacci(" + n + ") = " + fibonacci(n)); }}Count Primes Less than N
public class CountPrimes {
public int countPrimes(int n) {
if (n <= 2) return 0;
boolean[] isPrime = new boolean[n];
for (int i = 2; i < n; i++) {
isPrime[i] = true;
}
for (int i = 2; i * i < n; i++) {
if (!isPrime[i]) continue;
for (int j = i * i; j < n; j += i) {
isPrime[j] = false;
}
}
int count = 0;
for (int i = 2; i < n; i++) {
if (isPrime[i]) count++;
}
return count;
}
public static void main(String[] args) {
CountPrimes cp = new CountPrimes();
int n = 10;
int primeCount = cp.countPrimes(n);
System.out.println("Number of primes less than " + n + ": " + primeCount);
}
}Reverse a String (Iterative & Recursive)
public class StringReversal {
public static String reverseIterative(String str) {
StringBuilder reversed = new StringBuilder();
for (int i = str.length() - 1; i >= 0; i--) {
reversed.append(str.charAt(i));
}
return reversed.toString();
}
public static String reverseRecursive(String str) {
if (str == null || str.isEmpty()) {
return str;
}
return reverseRecursive(str.substring(1)) + str.charAt(0);
}
public static void main(String[] args) {
String input = "hello";
String reversedIterative = reverseIterative(input);
String reversedRecursive = reverseRecursive(input);
System.out.println("Iterative: " + reversedIterative);
System.out.println("Recursive: " + reversedRecursive);
}
}Count Primes Less than N
public class PrimeCounter {
public static int countPrimes(int n) {
if (n <= 2) {
return 0;
}
boolean[] isPrime = new boolean[n];
for (int i = 2; i < n; i++) {
isPrime[i] = true;
}
for (int i = 2; i * i < n; i++) {
if (!isPrime[i]) {
continue;
}
for (int j = i * i; j < n; j += i) {
isPrime[j] = false;
}
}
int count = 0;
for (int i = 2; i < n; i++) {
if (isPrime[i]) {
count++;
}
}
return count;
}
public static void main(String[] args) {
int n = 10;
int primeCount = countPrimes(n);
System.out.println("Number of primes less than " + n + ": " + primeCount);
}
}