HDU 1556 Color the ball（线段树）

来源：互联网发布：知乎帐号异常编辑：程序博客网时间：2024/06/06 12:43

思路:
法一：直接标记两个端点最后一直用dp[i]+=dp[i+1],向后推即可。
法二：线段树区间更新。

#include<map>#include<queue>#include<cmath>#include<iostream>#include<cstdio>#include<stack>#include<cstring>#include<algorithm>#define LL __int64#define inf 0x3f3f3f3f#define ls l,mid,rt<<1#define rs mid+1,r,rt<<1|1const double PI=acos(-1.0);using namespace std;#define mod 1000000007int sum[200010*5],lazy[5*200010];void Pushdown(int rt,int len){    if(lazy[rt]){        sum[rt<<1]+=(len-(len>>1))*lazy[rt];        sum[rt<<1|1]+=lazy[rt]*(len>>1);        lazy[rt<<1|1]+=lazy[rt];        lazy[rt<<1]+=lazy[rt];        lazy[rt]=0;    }}void Pushup(int rt){    sum[rt]=sum[rt<<1|1]+sum[rt<<1];}void Updata(int a,int b,int l,int r,int rt){    if(a<=l&&b>=r){        sum[rt]+=(r-l+1);        lazy[rt]+=1;        return ;    }    Pushdown(rt,r-l+1);    int mid=(l+r)>>1;    if(a<=mid)        Updata(a,b,ls);    if(b>mid)        Updata(a,b,rs);    Pushup(rt);}int so(int x,int l,int r,int rt){    if(l==r){        return sum[rt];    }    Pushdown(rt,r-l+1);    int mid=(l+r)>>1;    int ans=0;    if(x<=mid){        return ans+=so(x,ls);    }    else        return ans+=so(x,rs);}int main(){    int n,m,i,j,k,a,b;    while(~scanf("%d",&n)&&n){        memset(sum,0,sizeof(sum));        memset(lazy,0,sizeof(lazy));        //ini(1,n,1);        for(i=0;i<n;i++){            scanf("%d%d",&a,&b);            Updata(a,b,1,n,1);        }        for(i=1;i<=n;++i){            printf(i==n?"%d\n":"%d ",so(i,1,n,1));        }    }    return 0;}

0 0