add lzy

computer/computer.java

@@ -5,8 +5,46 @@ import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
 
 public class computer {
+    public static int convertToDecimal(String number, int base) {
+        int decimalValue = 0;
+        int power = 0;
 
+        for (int i = number.length() - 1; i >= 0; i--) {
+            char digit = number.charAt(i);
+            int digitValue;
 
+            if (Character.isDigit(digit)) {
+                digitValue = digit - '0';
+            } else {
+                digitValue = Character.toUpperCase(digit) - 'A' + 10; // A-F
+            }
+
+            decimalValue += digitValue * Math.pow(base, power);
+            power++;
+        }
+
+        return decimalValue;
+    }
+
+    public static String convertFromDecimal(int number, int base) {
+        StringBuilder result = new StringBuilder();
+
+        if (number == 0) {
+            return "0";
+        }
+
+        while (number > 0) {
+            int remainder = number % base;
+            if (remainder < 10) {
+                result.append((char) ('0' + remainder));
+            } else {
+                result.append((char) ('A' + remainder - 10));
+            }
+            number /= base;
+        }
+
+        return result.reverse().toString();
+    }
     public static void main(String[] args) {
         JFrame frame = new JFrame("进制转换器");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);