Added java and CPP codes

C++/Math and Others/Roman to Integer.cpp

@@ -0,0 +1,45 @@
+#include <bits/stdc++.h>
+
+class Solution
+{
+public:
+    int romanToInt(char c)
+    {
+        switch (c)
+        {
+        case 'I':
+            return 1;
+        case 'V':
+            return 5;
+        case 'X':
+            return 10;
+        case 'L':
+            return 50;
+        case 'C':
+            return 100;
+        case 'D':
+            return 500;
+        case 'M':
+            return 1000;
+        default:
+            return 0;
+        }
+    }
+
+    int romanToInt(string s)
+    {
+        int num = 0;
+        for (int i = 0; i < s.size(); i++)
+        {
+            if (i < s.size() - 1 && romanToInt(s[i]) < romanToInt(s[i + 1]))
+            {
+                num -= romanToInt(s[i]);
+            }
+            else
+            {
+                num += romanToInt(s[i]);
+            }
+        }
+        return num;
+    }
+};

Java/Patterns/DiamondPattern.java

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+import java.util.Scanner;
+
+public class DiamondPattern {
+    public static void main(String args[]) {
+        int row, i, j, space = 1;
+        System.out.print("Enter the number of rows you want to print: ");
+        Scanner sc = new Scanner(System.in);
+        row = sc.nextInt();
+        space = row - 1;
+        for (j = 1; j <= row; j++) {
+            for (i = 1; i <= space; i++) {
+                System.out.print(" ");
+            }
+            space--;
+            for (i = 1; i <= 2 * j - 1; i++) {
+                System.out.print("*");
+            }
+            System.out.println("");
+        }
+        space = 1;
+        for (j = 1; j <= row - 1; j++) {
+            for (i = 1; i <= space; i++) {
+                System.out.print(" ");
+            }
+            space++;
+            for (i = 1; i <= 2 * (row - j) - 1; i++) {
+                System.out.print("*");
+            }
+            System.out.println("");
+        }
+    }
+}

Java/Patterns/PyramidPattern.java

@@ -0,0 +1,27 @@
+public class PyramidPattern  
+{    
+public static void main(String args[])   
+{    
+//i for rows and j for columns      
+//row denotes the number of rows you want to print  
+int i, j, row = 6;       
+//Outer loop work for rows  
+for (i=0; i<row; i++)   
+{  
+//inner loop work for space      
+for (j=row-i; j>1; j--)   
+{  
+//prints space between two stars  
+System.out.print(" ");   
+}   
+//inner loop for columns  
+for (j=0; j<=i; j++ )   
+{   
+//prints star      
+System.out.print("* ");   
+}   
+//throws the cursor in a new line after printing each line  
+System.out.println();   
+}   
+}   
+}  

Java/Patterns/TrianglePattern.java

@@ -0,0 +1,19 @@
+public class TrianglePattern {
+
+    public static void tringlePattern(int n) {
+        for (int i = 1; i <= n; i++) {
+            for (int j = 1; j <= i; j++) {
+                if ((i + j) % 2 == 0) {
+                    System.out.print("1");
+                } else {
+                    System.out.print("0");
+                }
+            }
+            System.out.println();
+        }
+    }
+
+    public static void main(String args[]) {
+        tringlePattern(5);
+    }
+}