POJ 1177 Picture(求周长并)

题目链接

看的HH的题解。。周长有两部分组成，横着和竖着的，横着通过，sum[1] - last来计算，竖着的通过标记，记录有多少段。

 #include <cstdio>
 #include <cstring>
 #include <string>
 #include <cmath>
 #include <algorithm>
 using namespace std;
 #define maxn 10000
 #define lson l , m, rt<<1
 #define rson m+1, r,rt<<1|1
 int que[maxn*];
 int sum[maxn*];
 int cnt[maxn*];
 bool lbd[maxn*] , rbd[maxn*];
 int numseg[maxn*];
 struct node
 {
     int lx,rx,y;
     int s;
     node() {}
     node(int a,int b,int c,int d):lx(a),rx(b),y(c),s(d) {}
     bool operator < (const node &S) const
     {
         if(y == S.y) return s > S.s;
         return y < S.y;
     }
 } mat[maxn];
 int bin(int x,int n)
 {
     int str,end,mid;
     str = ,end = n;
     while(str <= end)
     {
         mid = (str+end)/;
         if(que[mid] == x)
             return mid;
         else if(que[mid] > x)
             end = mid - ;
         else
             str = mid + ;
     }
     return mid;
 }
 void pushup(int rt,int l,int r)
 {
     if(cnt[rt])
     {
         lbd[rt] = rbd[rt] = ;
         sum[rt] = que[r+] - que[l];
         numseg[rt] = ;
     }
     else if (l == r)
     {
         sum[rt] = numseg[rt] = lbd[rt] = rbd[rt] = ;
     }
     else
     {
         lbd[rt] = lbd[rt<<];
         rbd[rt] = rbd[rt<<|];
         sum[rt] = sum[rt<<] + sum[rt<<|];
         numseg[rt] = numseg[rt<<] + numseg[rt<<|];
         if (lbd[rt<<|] && rbd[rt<<]) numseg[rt] -= ;
     }
 }
 void update(int L,int R,int c,int l,int r,int rt)
 {
     if(L <= l&&r <= R)
     {
         cnt[rt] += c;
         pushup(rt,l,r);
         return ;
     }
     int m = (l+r)>>;
     if(L <= m)
         update(L,R,c,lson);
     if(R > m)
         update(L,R,c,rson);
     pushup(rt,l,r);
 }
 int main()
 {
     int n,num,i,l,r;
     int a,b,c,d;
     while(scanf("%d",&n)!=EOF)
     {
         if(!n) break;
         num = ;
         for(i = ; i < n; i ++)
         {
             scanf("%d%d%d%d",&a,&b,&c,&d);
             que[num] = a;
             mat[num ++] = node(a,c,b,);
             que[num] = c;
             mat[num ++] = node(a,c,d,-);
         }
         sort(que,que+num);
         sort(mat,mat+num);
         int k = ;
         for(i = ; i < num; i ++)
         {
             if(que[i] != que[i-])
                 que[k++] = que[i];
         }
         int ans = ,last = ;
         memset(cnt,,sizeof(cnt));
         memset(sum,,sizeof(sum));
         memset(lbd,,sizeof(lbd));
         memset(rbd,,sizeof(rbd));
         for(i = ; i < num; i ++)
         {
             l = bin(mat[i].lx,k-);
             r = bin(mat[i].rx,k-)-;
             if(l <= r)
                 update(l,r,mat[i].s,,k-,);
             ans += numseg[] * (mat[i+].y - mat[i].y);
             ans += abs(sum[] - last);
             last = sum[];
         }
         printf("%d\n",ans);
     }
     return ;
 }