Find out second largest element of an unsorted array?

   Find out second largest element of an unsorted array?


#include<stdio.h>
 #include<stdlib.h>
 main()
 {
 int a[100],i,num,n,mx;
printf("enter number of elements to be entered");
 scanf("%d",&n);
 printf("enter numbers");
 for(i=0;i<n;i++)
 scanf("%d",&a[i]);
mx=a[0];
num=a[0];
 for(i=0;i<n;i++)
 {
if(a[i]>num)
 {
 if(a[i]>mx)
 {num=mx;
 max=a[i];}
if(a[i]<mx)
 num=a[i];
 }
}
 printf("second largest no. is %d",num);
 system("pause");

}