#include <bits/stdc++.h> using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- int N; ll Y[101010]; ll dp[101010][4]; //left,keep(ok),keep(ng),right void solve() { int i,j,k,l,r,x,y; string s; cin>>N; FOR(i,N) cin>>Y[i]; sort(Y,Y+N); FOR(i,N+1) dp[i][0]=dp[i][1]=dp[i][2]=dp[i][3]=1LL<<60; dp[0][2]=0; dp[0][3]=Y[1]-Y[0]; for(i=1;i<N;i++) { dp[i][0]=min(dp[i][0],dp[i-1][1]+(Y[i]-Y[i-1])); dp[i][0]=min(dp[i][0],dp[i-1][2]+(Y[i]-Y[i-1])); dp[i][1]=min(dp[i][1],dp[i-1][3]); dp[i][2]=min(dp[i][2],dp[i-1][0]); dp[i][2]=min(dp[i][2],dp[i-1][1]); if(i<N-1) { dp[i][3]=min(dp[i][3],dp[i-1][0]+(Y[i+1]-Y[i])); dp[i][3]=min(dp[i][3],dp[i-1][1]+(Y[i+1]-Y[i])); } } cout<<min(dp[N-1][0],dp[N-1][1])<<endl; } int main(int argc,char** argv){ string s;int i; if(argc==1) ios::sync_with_stdio(false), cin.tie(0); FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin); cout.tie(0); solve(); return 0; }