Calculate The Smallest Number In The Given Array Using Java

import java.io.*; 
import java.text.*; 

class ssva22 
{ 
public static void main(String arg[]) throws IOException 
{ 
double a[]=new double[20],temp=0; 
int i,j,n; 
BufferedReader obj=new BufferedReader(new InputStreamReader(System.in)); 
System.out.println("\n LOWEST NUMBER"); 
System.out.println(" -------------"); 
System.out.print("\nENTER HOW MANY NUMBER : "); 
n=Integer.parseInt(obj.readLine()); 
NumberFormat nf=NumberFormat.getInstance(); 
nf.setMaximumFractionDigits(2); 
nf.setMinimumFractionDigits(0); 
System.out.println("\nENTER THE NUMBERS\n"); 

for(i=0;i<n;i++) 
{ 
a[i]=Double.parseDouble(obj.readLine()); 
} 
for(i=0;i<n-1;i++) 
{ 
for(j=i+1;j<n;j++) 
{ 
if(a[i]<a[j]) 
{ 
temp=a[i]; 
a[i]=a[j]; 
a[j]=temp; 
} 
} 
} 
System.out.println("\nTHE LOWEST NUMBER IS : "+nf.format(a[i])); 
System.out.println("\n"); 
} 
}