BZOJ 1293 生日礼物(尺取法)

把坐标离散化之后就是很普通的尺取法啦。

# include <cstdio>

# include <cstring>

# include <cstdlib>

# include <iostream>

# include <vector>

# include <queue>

# include <stack>

# include <map>

# include <set>

# include <cmath>

# include <algorithm>

using namespace std;

# define lowbit(x) ((x)&(-x))

# define pi 3.1415926535

# define eps 1e-

# define MOD

# define INF

# define mem(a,b) memset(a,b,sizeof(a))

# define FOR(i,a,n) for(int i=a; i<=n; ++i)

# define FO(i,a,n) for(int i=a; i<n; ++i)

# define bug puts("H");

# define lch p<<,l,mid

# define rch p<<|,mid+,r

# define mp make_pair

# define pb push_back

typedef pair<int,int> PII;

typedef vector<int> VI;

# pragma comment(linker, "/STACK:1024000000,1024000000")

typedef long long LL;

int Scan() {

    int res=, flag=;

    char ch;

    if((ch=getchar())=='-') flag=;

    else if(ch>=''&&ch<='') res=ch-'';

    while((ch=getchar())>=''&&ch<='')  res=res*+(ch-'');

    return flag?-res:res;

}

void Out(int a) {

    if(a<) {putchar('-'); a=-a;}

    if(a>=) Out(a/);

    putchar(a%+'');

}

const int N=;

//Code begin...

struct Node{int c; LL pos;}node[N];

int vis[], num;

bool comp(Node a, Node b){return a.pos<b.pos;}

int main ()

{

    LL ans=(LL)<<;

    int n, k, t;

    n=Scan(); k=Scan();

    FOR(i,,k) {

        t=Scan();

        while (t--) node[++num].pos=Scan(), node[num].c=i;

    }

    sort(node+,node+n+,comp);

    num=;

    int l=, r=;

    while () {

        while (num<k) {

            ++r;

            if (r>n) break;

            if (vis[node[r].c]==) ++num;

            ++vis[node[r].c];

        }

        if (r>n) break;

        ans=min(ans,node[r].pos-node[l].pos);

        --vis[node[l].c];

        if (vis[node[l].c]==) --num;

        ++l;

    }

    printf("%lld\n",ans);

    return ;

}