usaco sort3

#include<stdio.h>int a[1001],ans;void qs(int l,int r){int i,j,t,mid;i=l;j=r;mid=a[(l+r)/2];while (i<j) {while (a[i]<mid) i++;while (a[j]>mid) j--;if (i<=j) {t=a[i];a[i]=a[j];a[j]=t;i++;j--;}}if (l<j) qs(l,j);if (i<r) qs(i,r);}int main(){freopen("sort3.in","r",stdin);freopen("sort3.out","w",stdout);int n,b[1001],i,j,t;scanf("%d",&n);for (i=1;i<=n;i++) {scanf("%d",&a[i]);b[i]=a[i];}qs(1,n);for (i=1;i<n;i++) {for (j=i+1;j<=n;j++) {if (a[i]!=a[j]) {if (a[i]==b[j] && a[j]==b[i]) {ans++;t=b[i];b[i]=b[j];b[j]=t;}}}}for (i=1;i<=n;i++) {if (a[i]!=1) break;if (b[i]!=1) ans+=2;}printf("%d\n",ans);return 0;}