POJ3067 Japan tree-like array

There are n cities on the left of a city, from top to bottom and M cities on the right.

Now to build K high-speed rail, the starting point on the left, the end to the right,

Ask how many intersections you have (only 2 lines pass at any intersection).

Sort + Tree-like array, insert points to ask paragraph.

After sorting, click Start from small to large sweep again,

A[J] Indicates the number of end points in the front I line, which is J.

C[J] A tree-like array of a[j].

Note: The final result is to use a long long

1#include <algorithm>2#include <cstdio>3#include <cstring>4 using namespacestd;5 Const intmaxn= ++5;6 intC[MAXN];7 structEdge8 {9     intu,v;Ten}edge[maxn*MAXN]; One intn,m; A BOOLCMP (Edge I,edge j) - { -     if(i.u==j.u) the         returni.v<j.v; -     returni.u<j.u; - } - intLowbit (intx) + { -     returnx& (-x); + } A intSumintx) at { -     inttemp=0; -      while(x>0){ -temp+=C[x]; -x-=lowbit (x); -     } in     returntemp; - } to voidUpdateintXintnum) + { -      while(x<=m) { thec[x]+=num; *x+=lowbit (x); $     }Panax Notoginseng } - intMain () the { +     inttest; A     intcas=0; thescanf"%d",&test); +      while(test--){ -cas++; $         intK; $scanf"%d%d%d",&n,&m,&k); -          for(intI=1; i<=k;i++) -scanf"%d%d",&edge[i].u,&edge[i].v); theSort (edge+1, edge+k+1, CMP); -Memset (c,0,sizeof(c));Wuyi         Long Longans=0; the          for(intI=1; i<=k;i++){ -Update (EDGE[I].V,1); Wuans+= (Long Long) (I-sum (EDGE[I].V)); -         } Aboutprintf"Test Case%d:%i64d\n", Cas,ans); $     } -     return 0; -}

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POJ3067 Japan tree-like array