bzoj3062[Usaco2013 Feb]Taxi*

 1 #include <cstdio>
 2 #include <cstring>
 3 #include <algorithm>
 4 #include <queue>
 5 #define inc(i,j,k) for(int i=j;i<=k;i++)
 6 #define maxn 100010
 7 using namespace std;
 8 
 9 inline int read(){
10     char ch=getchar(); int f=1,x=0;
11     while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1; ch=getchar();}
12     while(ch>=‘0‘&&ch<=‘9‘)x=x*10+ch-‘0‘,ch=getchar();
13     return f*x;
14 }
15 int n,m,a[maxn],b[maxn]; long long ans;
16 int main(){
17     n=read(); m=read(); inc(i,1,n)a[i]=read(),b[i]=read(); inc(i,1,n)ans+=abs(a[i]-b[i]);
18     a[++n]=m; b[n]=0; sort(a+1,a+n+1); sort(b+1,b+n+1); inc(i,1,n)ans+=abs(a[i]-b[i]);
19     printf("%lld",ans); return 0;
20 }