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#include<bits/stdc++.h>
namespace ZDY{
    #define il __inline__ __attribute__ ((always_inline))
    #define ll long long
    #define MB template <class T>il
    #define Fur(i,x,y) for(int i=x;i<=y;i++)
    #define inf 0x3f3f3f3f
    MB T ABS(T x){return x>0?x:-x;}
    MB T MIN(T x,T y){return x<y?x:y;}
}using namespace ZDY;using namespace std;
namespace IO{const char* ln="\n";const int str=1<<20;struct IN{char buf[str],*s,*t;bool _;IN():s(buf),t(buf),_(0){}il char gc(){return s==t&&((t=(s=buf)+fread(buf,1,str,stdin))==s)?EOF:(*s++);}IN&operator>>(char&ch){if(_)return *this;char c;while((c=gc())!=EOF&&isspace(c));if(c==EOF)_=1;else ch=c;return *this;}IN& operator>>(char* ch){if(_)return *this;char c;while((c=gc())!=EOF&&isspace(c));if(c==EOF)return _=1,*this;*ch=c;ch++;while((c=gc())!=EOF&&!isspace(c))*ch=c,ch++;if(c==EOF)_=1;return *this;}IN& operator>>(string& ch){if(_)return *this;char c;while((c=gc())!=EOF&&isspace(c));if(c==EOF)return _=1,*this;ch+=c;while((c=gc())!=EOF&&!isspace(c))ch+=c;if(c==EOF)_=1;return *this;}template<typename T>IN&operator>>(T&x){if(_)return *this;char c=gc();bool ff=0;while(c!=EOF&&(c<'0'||c>'9'))ff^=(c=='-'),c=gc();if(c==EOF){_=1;return *this;}x=0;while(c!=EOF&&'0'<=c&&c<='9')x=(x<<3)+(x<<1)+c-48,c=gc();if(c==EOF)_=1;if(ff)x=-x;return *this;}}in;struct OUT{char buf[str],*s,*t;OUT():s(buf),t(buf+str){}~OUT(){fwrite(buf,1,s-buf,stdout);}void pt(char c){(s==t)?(fwrite(s=buf,1,str,stdout),*s++=c):(*s++=c);}OUT&operator<<(const char*s){while(*s)pt(*s++);return *this;}OUT&operator<<(char*s){while(*s)pt(*s++);return *this;}OUT&operator<<(string s){for(int i=0;s[i];i++)pt(s[i]);return *this;}template<typename T>OUT&operator<<(T x){if(!x)return pt('0'),*this;if(x<0)pt('-'),x=-x;char a[30],t=0;while(x)a[t++]=x%10,x/=10;while(t--)pt(a[t]+'0');return *this;}}out;}using namespace IO;
#define N 100011
int a[N],b[N],n;
ll f[N];
il int get(int x,int y){return (x==y)?inf:ABS(x-y);}
int main(){
    in>>n;
    Fur(i,1,n)in>>a[i]>>b[i];
    std::sort(a+1,a+n+1);
    std::sort(b+1,b+n+1);
    Fur(i,1,n){
        f[i]=f[i-1]+get(a[i],b[i]);
        f[i]=MIN(f[i],f[i-2]+get(a[i],b[i-1])+get(a[i-1],b[i]));
        f[i]=MIN(f[i],f[i-3]+get(a[i],b[i-2])+get(a[i-2],b[i])+get(a[i-1],b[i-1]));
        f[i]=MIN(f[i],f[i-3]+get(a[i],b[i-1])+get(a[i-1],b[i-2])+get(a[i-2],b[i]));
        f[i]=MIN(f[i],f[i-3]+get(a[i],b[i-2])+get(a[i-1],b[i])+get(a[i-2],b[i-1]));
    }
    out<<f[n]<<ln;
}
LG 2507 [SCOI2008]配对
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