Calculating Run Time

Author: sb255

Topics/CalculatingRunTime.java

@@ -0,0 +1,86 @@
+
+/*----- Checking the run time of an Array using different approaches -----*/
+
+import java.util.*; 
+import java.util.concurrent.TimeUnit;
+
+
+public class CalculatingRunTime {
+    
+   public static void main(String args[]){
+        
+        int arr[] = new int[(Integer.MAX_VALUE)/10000];
+        
+        for(int i=(Integer.MAX_VALUE)/10000; i>0; i--){
+            arr[(Integer.MAX_VALUE)/10000 - i] = i; 
+        }
+        
+        /*--- Calculating the run time for sorting using nested for loops: ---*/
+        
+        long timeStarts = System.currentTimeMillis();  //Time starts here
+        
+            for(int i=0; i<arr.length; i++){
+                for(int j=i+1; j<arr.length; j++){
+                    if(arr[i]>arr[j]) {
+                        int bucket = arr[i];
+                        arr[i] = arr[j]; 
+                        arr[j] = bucket; 
+                    }
+                }
+            }
+        
+        System.out.print("The sorted array in ASC order is:");
+        
+        for(int i=0; i<arr.length; i++){
+            System.out.print(" "+arr[i]);
+        }
+        
+        long timeEnds = System.currentTimeMillis();   //Time ends here
+        
+        long timeInSeconds = TimeUnit.MILLISECONDS.toSeconds(timeEnds - timeStarts);
+        
+        System.out.printf("%nThe Time taken in seconds is: "+timeInSeconds+" seconds%n");
+        
+        
+        
+        /*--- Checking run time for Array sorting using inbuilt sorting method: ---*/
+        
+        
+        
+        int arr2[] = new int[(Integer.MAX_VALUE)/10000];
+        
+        for(int i=(Integer.MAX_VALUE)/10000; i>0; i--){
+            arr2[(Integer.MAX_VALUE)/10000 - i] = i; 
+        }
+        
+        long timeStarts2 = System.currentTimeMillis();   //Time starts here
+        
+        Arrays.sort(arr2);
+        
+        System.out.print("The sorted array in ASC order is:");
+        
+        for(int i=0; i<arr2.length; i++){
+            System.out.print(" "+arr2[i]);
+        }
+       
+        long timeEnds2 = System.currentTimeMillis();   //Time ends here
+        
+        long timeInSeconds2 = TimeUnit.MILLISECONDS.toSeconds(timeEnds2 - timeStarts2);
+        
+        System.out.printf("%nThe Time taken in seconds is: "+timeInSeconds2+" seconds%n");
+        
+    }
+   
+    
+}
+
+/*
+* Worst case:
+*
+* The Run time for for-loop came out to be: 21 seconds 
+* The Run time for inbuilt sort came out to be: 1 second
+*
+*
+*/
+
+