【HDU】3911 Black And White 
  1 #include<cstdio>
  2 #define MAXN 100010
  3 struct node
  4 {
  5     int left0,right0,v0,left1,right1,v1,lazy;
  6 };
  7 node tree[MAXN<<2];
  8 inline int MAX(int x,int y)
  9 {
 10     return x>y?x:y;
 11 }
 12 inline int MIN(int x,int y)
 13 {
 14     return x>y?y:x;
 15 }
 16 inline void swap(int &x,int &y)
 17 {
 18     int temp=x;
 19     x=y;
 20     y=temp;
 21 }
 22 inline void PushUp(int mid,int L,int R,int rt)
 23 {
 24     tree[rt].left0=tree[rt<<1].left0;
 25     tree[rt].left1=tree[rt<<1].left1;
 26     tree[rt].right0=tree[rt<<1|1].right0;
 27     tree[rt].right1=tree[rt<<1|1].right1;
 28     if(tree[rt].left0==mid-L+1)
 29         tree[rt].left0+=tree[rt<<1|1].left0;
 30     if(tree[rt].left1==mid-L+1)
 31         tree[rt].left1+=tree[rt<<1|1].left1;
 32     if(tree[rt].right0==R-mid)
 33         tree[rt].right0+=tree[rt<<1].right0;
 34     if(tree[rt].right1==R-mid)
 35         tree[rt].right1+=tree[rt<<1].right1;
 36     tree[rt].v0=MAX(tree[rt<<1].v0,tree[rt<<1|1].v0);
 37     tree[rt].v0=MAX(tree[rt].v0,tree[rt<<1].right0+tree[rt<<1|1].left0);
 38     tree[rt].v1=MAX(tree[rt<<1].v1,tree[rt<<1|1].v1);
 39     tree[rt].v1=MAX(tree[rt].v1,tree[rt<<1].right1+tree[rt<<1|1].left1);
 40 }
 41 void Build(int L,int R,int rt)
 42 {
 43     tree[rt].lazy=0;
 44     if(L==R)
 45     {
 46         scanf("%d",&tree[rt].v1);
 47         tree[rt].left1=tree[rt].right1=tree[rt].v1;
 48         tree[rt].left0=tree[rt].right0=tree[rt].v0=tree[rt].v1^1;
 49     }
 50     else
 51     {
 52         int mid=(L+R)>>1;
 53         Build(L,mid,rt<<1);
 54         Build(mid+1,R,rt<<1|1);
 55         PushUp(mid,L,R,rt);
 56     }
 57 }
 58 void Init(int rt)
 59 {
 60     swap(tree[rt].left0,tree[rt].left1);
 61     swap(tree[rt].right0,tree[rt].right1);
 62     swap(tree[rt].v0,tree[rt].v1);
 63 }
 64 inline void PushDown(int mid,int L,int R,int rt)
 65 {
 66     if(tree[rt].lazy)
 67     {
 68         tree[rt<<1].lazy^=1;
 69         tree[rt<<1|1].lazy^=1;
 70         Init(rt<<1);
 71         Init(rt<<1|1);
 72         tree[rt].lazy=0;
 73     }
 74 }
 75 void Change(int x,int y,int L,int R,int rt)
 76 {
 77     if(x<=L&&R<=y)
 78     {
 79         tree[rt].lazy^=1;
 80         Init(rt);
 81     }
 82     else
 83     {
 84         int mid=(L+R)>>1;
 85         PushDown(mid,L,R,rt);
 86         if(mid>=x)
 87             Change(x,y,L,mid,rt<<1);
 88         if(y>mid)
 89             Change(x,y,mid+1,R,rt<<1|1);
 90         PushUp(mid,L,R,rt);
 91     }
 92 }
 93 int Query(int x,int y,int L,int R,int rt)
 94 {
 95     if(x<=L&&R<=y)
 96         return tree[rt].v1;
 97     int mid=(L+R)>>1,ans=0;
 98     PushDown(mid,L,R,rt);
 99     if(mid>=x)
100         ans=MAX(ans,Query(x,y,L,mid,rt<<1));
101     if(y>mid)
102         ans=MAX(ans,Query(x,y,mid+1,R,rt<<1|1));
103     return MAX(ans,MIN(mid-x+1,tree[rt<<1].right1)+MIN(y-mid,tree[rt<<1|1].left1));
104 }
105 int main()
106 {
107     int n,m,type,x,y;
108     while(~scanf("%d",&n))
109     {
110         Build(1,n,1);
111         scanf("%d",&m);
112         while(m--)
113         {
114             scanf("%d%d%d",&type,&x,&y);
115             if(type)
116                 Change(x,y,1,n,1);
117             else
118                 printf("%d\n",Query(x,y,1,n,1));
119         }
120     }
121     return 0;
122 }
posted on 2012-05-25 01:08  DrunBee  阅读(430)  评论(0)  编辑  收藏  举报