View Code of Problem 1076

#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
struct node
{
	int x,t;
}edge[1005];
int cmp(node a,node b)
{
	return a.x<b.x;
}
int c,h,b;
int f[1005][1005][2];
int main()
{
	scanf("%d %d %d",&c,&h,&b);
	for(int i=1;i<=c;i++)
	{
		scanf("%d %d",&edge[i].x,&edge[i].t);
	}
	sort(edge+1,edge+1+c,cmp);
	memset(f,0x3f,sizeof(f));
	f[1][c][0]=max(edge[1].x,edge[1].t);
	f[1][c][1]=max(edge[c].x,edge[c].t);
	for(int i=1;i<=c;i++)
	{
		for(int j=c;j>=i;j--)
		{
			if(i==1&&j==c)continue;
			if(i==1)
			{
				f[i][j][0]=max(f[i][j+1][1]+edge[j+1].x-edge[i].x,edge[i].t);
				f[i][j][1]=max(f[i][j+1][1]+edge[j+1].x-edge[j].x,edge[j].t);
			}else if(j==h)
			{
				f[i][j][0]=max(f[i-1][j][0]+edge[i].x-edge[i-1].x,edge[i].t);
				f[i][j][1]=max(f[i-1][j][0]+edge[j].x-edge[i-1].x,edge[j].t);
			}else
			{
				f[i][j][0]=min(max(f[i-1][j][0]+edge[i].x-edge[i-1].x,edge[i].t),max(f[i][j+1][1]+edge[j+1].x-edge[i].x,edge[i].t));
				f[i][j][1]=min(max(f[i-1][j][0]+edge[j].x-edge[i-1].x,edge[j].t),max(f[i][j+1][1]+edge[j+1].x-edge[j].x,edge[j].t));
			}
		}
	}
	int ans=0x3f3f3f3f;
	for(int i=1;i<=c;i++)
	{
		ans=min(ans,min(f[i][i][0]+abs(edge[i].x-b),f[i][i][1]+abs(edge[i].x-b)));
	}
	printf("%d",ans);
}