void insertion_sort(int arr[], int len)
{
int i,j,key;
for (i=1;i<len;i++)
{
key = arr[i];
j=i-1;
while((j>=0) && (arr[j]>key))
{
arr[j+1] = arr[j];
j--;
}
arr[j+1] = key;
}
}