"Linglong Cup" ACM competition Round #7 B--Capture (and check + priority queue)

Test instructions: Initially there was a capital of 1, with n operations

+v says there's a new city connected to the city of V,

-V means the city of V is disconnected and the sub-city of V is disconnected

Number of cities with the lowest number of outputs with the same output numbers per output after each operation to the capital 1 farthest from the city

The input data is guaranteed to be correct, each time the city added and deleted must be connected to the capital.

Puzzle: Only need to know the furthest and least numbered cities each time, so use priority queue storage directly

If it is +v use and check set (not path compression) to add and then join the priority queue, and then directly pop the first element is the result

If it is-V Point v to 0, then the first element of the priority queue pops up

If he is connected with 1 is the answer, otherwise will he to 0 this road point all connected 0 delete him, continue to pop

Note that there is a trick that if no city is connected to 1, the answer is 1.

#include <Set>#include<map>#include<queue>#include<stack>#include<cmath>#include<vector>#include<string>#include<cstdio>#include<cstring>#include<iomanip>#include<stdlib.h>#include<iostream>#include<algorithm>using namespacestd;#defineEPS 1E-8/*Note that there may be output -0.000*/#defineSGN (x) (X<-eps -1:x<eps? 0:1)//X is a comparison of two floating-point numbers, note the return integer#defineCVS (x) (x > 0.0 x+eps:x-eps)//floating point Conversion#defineZero (x) (((x) >0? ( x):-(x)) <eps)//determine if it equals 0#defineMul (A, B) (a<<b)#defineDir (A, B) (a>>b)typedefLong Longll;typedef unsignedLong Longull;Const intinf=1<< -;Constll inf=1ll<< -;Const DoublePi=acos (-1.0);Const intmod=1e9+7;Const intmax=2e5+7;structnode{intKey,value;//storage number and distance from 1    BOOL operator< (ConstNode &c)Const//The distance of the large number of small priority    {        if(value==c.value)returnKey>C.key; returnvalue<C.value; }};p Riority_queue<structNode>ans;intFat[max],val[max];CharStr[max];voidInit (intN) {     while(!ans.empty ()) Ans.pop (); node temp;//Initializes an element 1 at the bottom of the queueTemp.value=0; Temp.key=1;    Ans.push (temp);  for(intI=0; i<=n;++i) {Fat[i]=i; Val[i]=0; }    return;}intFind (intx) {    if(x==Fat[x])returnFat[x]; returnFind (fat[x]);}voidSolveadd (intFintS//+{Node temp; Fat[s]=F; Val[s]=val[f]+1; Temp.key=s; Temp.value=Val[s];    Ans.push (temp); return;}voidSolvesub (intF//-{Node temp; ints; FAT[F]=0;  while(!Ans.empty ()) {Temp=Ans.top (); if(Find (temp.key) = =1)            return; S=Temp.key;  while(fat[s]!=0)//The chain is assigned 0.{Fat[s]=0;    } ans.pop (); }    return;}intMain () {intt,n,m,coun;scanf ("%d",&t); node temp; while(t--) {scanf ("%d",&N); Init (n+1); Coun=1;  for(intI=0; i<n;++i) {GetChar (); scanf ("%c%d",&str[i],&m); if(str[i]=='+') {Solveadd (M,++Coun); }        Else{solvesub (M); } temp=Ans.top (); printf ("%d\n", Temp.key); }}return 0;}

"Linglong Cup" ACM competition Round #7 B--Capture (and check + priority queue)