hdu 1698 Just a Hook（成段更新）

题意：有t组测试数据，n为钩子长度（1<=n<=100000）,m为操作的次数。初始时，每个钩子的价值为1，操作由三个数字组成x,y,z表示把区间[x,y]的钩子变成的价值变成z（1代表铜，2银，3金）。

       使用了延迟标记type，表示当前区间的左右子儿子的价值为type，在更新到当前区间时，同时更新当前区间的valu，即type*当前区间的长度。

/*代码风格更新后*/#include <iostream>#include <cstdio>#include <cstring>using namespace std;#define LL(x) (x<<1)#define RR(x) (x<<1|1)#define MID(a,b) (a+((b-a)>>1))const int N=100005;struct node{int lft,rht;int valu,type;int mid(){return MID(lft,rht);}void fun(int tmp){type=tmp;valu=(rht-lft+1)*type;}};struct Segtree{node tree[N*4];void build(int lft,int rht,int ind){tree[ind].lft=lft;tree[ind].rht=rht;tree[ind].valu=rht-lft+1;tree[ind].type=1;if(lft!=rht){int mid=tree[ind].mid();build(lft,mid,LL(ind));build(mid+1,rht,RR(ind));}}void updata(int st,int ed,int ind,int type){int lft=tree[ind].lft,rht=tree[ind].rht;if(st<=lft&&rht<=ed) tree[ind].fun(type);else {if(tree[ind].type){tree[LL(ind)].fun(tree[ind].type);tree[RR(ind)].fun(tree[ind].type);tree[ind].type=0;}int mid=tree[ind].mid();if(st<=mid) updata(st,ed,LL(ind),type);if(ed>mid)  updata(st,ed,RR(ind),type);tree[ind].valu=tree[LL(ind)].valu+tree[RR(ind)].valu;}}}seg;int main(){int t,t_cnt=0;scanf("%d",&t);while(t--){int n,m,a,b,c;scanf("%d%d",&n,&m);seg.build(1,n,1);while(m--){scanf("%d%d%d",&a,&b,&c);seg.updata(a,b,1,c);}printf("Case %d: The total value of the hook is %d.\n",++t_cnt,seg.tree[1].valu);}return 0;}

/*代码风格更新前*/#include <iostream>#include <cstdio>using namespace std;const int N=100005;struct node{    int left,right,co,sum;    int mid(){return left+(right-left)/2;}    int dis(){return right-left+1;}    void change(int a)    {        co=a; sum=co*dis();    }};struct Segtree{    node tree[N*4];    void build(int left,int right,int r)    {        tree[r].left=left;  tree[r].right=right;        tree[r].co=1;      tree[r].sum=tree[r].dis();        if(left<right)        {            int mid=tree[r].mid();            build(left,mid,r*2);            build(mid+1,right,r*2+1);        }    }    void updata(int be,int end,int r,int co)    {        if(be<=tree[r].left&&tree[r].right<=end)        {            tree[r].change(co);        }        else        {            if(tree[r].co!=0)            {                tree[r*2].change(tree[r].co);                tree[r*2+1].change(tree[r].co);                tree[r].co=0;            }            int mid=tree[r].mid();            if(be<=mid) updata(be,end,r*2,co);            if(end>mid) updata(be,end,r*2+1,co);            tree[r].sum=tree[r*2].sum+tree[r*2+1].sum;        }    }}seg;int main(){    int t,t_cnt=0;    scanf("%d",&t);    while(t--)    {        int n,m;        scanf("%d%d",&n,&m);        seg.build(1,n,1);        for(int i=0;i<m;i++)        {            int x,y,z;            scanf("%d%d%d",&x,&y,&z);            seg.updata(x,y,1,z);        }        printf("Case %d: The total value of the hook is %d.\n",++t_cnt,seg.tree[1].sum);    }    return 0;}