dijkstra algorithm implementation need to be done properly

DSA_JAVA.iml

@@ -18,5 +18,6 @@
         </SOURCES>
       </library>
     </orderEntry>
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
   </component>
 </module>

src/Evaluate142.java

@@ -0,0 +1,41 @@
+import edu.princeton.cs.algs4.StdIn;
+
+import java.util.Stack;
+
+public class Evaluate142 {
+    public static void main(String[] args) {
+        Stack<String> ops = new Stack<>();
+        Stack<Double> vals = new Stack<>();
+        while (!StdIn.isEmpty()) {
+            String s = StdIn.readString();
+            if (s.equals("(")) {
+
+            } else if (s.equals("+")) {
+                ops.push(s);
+            } else if (s.equals("-")) {
+                ops.push(s);
+            } else if (s.equals("*")) {
+                ops.push(s);
+            } else if (s.equals("/")) {
+                ops.push(s);
+            } else if (s.equals("sqrt")) {
+                ops.push(s);
+            } else if (s.equals(")")) {
+                String op = ops.pop();
+                double v = vals.pop();
+                if (op.equals("+")) {
+                    v = vals.pop() + v;
+                } else if (op.equals("-")) {
+                    v = vals.pop() - v;
+                } else if (op.equals("*")) {
+                    v = vals.pop() * v;
+                } else if (op.equals("/")) {
+                    v = vals.pop() / v;
+                } else if (op.equals("sqrt")) {
+                    v = Math.sqrt(v);
+                }
+                vals.push(v);
+            }
+        }
+    }
+}

src/Flips.java

@@ -1,4 +1,5 @@
 import edu.princeton.cs.algs4.Counter;
+import edu.princeton.cs.algs4.Date;
 import edu.princeton.cs.algs4.StdOut;
 import edu.princeton.cs.algs4.StdRandom;
 

src/MemoryManagement104.java

@@ -0,0 +1,13 @@
+import edu.princeton.cs.algs4.Date;
+
+public class MemoryManagement104 {
+    public static void main(String[] args) {
+        Date a = new Date(12, 31, 1999);
+        System.out.println(a);
+        Date b = new Date(12,31,2001);
+        System.out.println(b);
+        b = a;
+        System.out.println(a);
+        System.out.println(b);
+    }
+}

src/Reverse.java

@@ -0,0 +1,15 @@
+import edu.princeton.cs.algs4.StdIn;
+import edu.princeton.cs.algs4.StdOut;
+
+import java.util.Stack;
+
+public class Reverse {
+    public static void main(String[] args) {
+        Stack<Integer> stack;
+        stack = new Stack<>();
+        while (!StdIn.isEmpty())
+            stack.push(StdIn.readInt());
+        while (!stack.isEmpty())
+            StdOut.println(stack.pop());
+    }
+}

src/Stats138.java

@@ -0,0 +1,27 @@
+import edu.princeton.cs.algs4.Bag;
+import edu.princeton.cs.algs4.StdIn;
+import edu.princeton.cs.algs4.StdOut;
+
+public class Stats138 {
+    public static void main(String[] args) {
+        Bag<Double> numbers = new Bag<>();
+        while (!StdIn.isEmpty()) {
+            numbers.add(StdIn.readDouble());
+        }
+        int N = numbers.size();
+
+        double sum = 0.0;
+        for (double x : numbers) {
+            sum += x;
+        }
+        double mean = sum/N;
+
+        sum = 0.0;
+        for (double x:numbers){
+            sum+= (x-mean) * (x-mean);
+        }
+        double std = Math.sqrt(sum/(N-1));
+        StdOut.printf("Mean: %.2f\n", mean);
+        StdOut.printf("Std dev: %.2f\n", std);
+    }
+}