/*
Things to notice:
1. do not calculate useless values
2. do not use similar names
Things to check:
1. submit the correct file
2. time (it is log^2 or log)
3. memory
4. prove your naive thoughts
5. long long
6. corner case like n=0,1,inf or n=m
7. check if there is a mistake in the ds or other tools you use
8. fileio in some oi-contest
9. module on time
10. the number of a same divisor in a math problem
11. multi-information and queries for dp and ds problems
*/
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
const int mod=998244353;
const int inf=0x3f3f3f3f;
int fa[1000005],siz_e[1000005],sizv[1000005],rel[1000005];
int find(int x)
{
if(fa[x]==x) return x;
return fa[x]=find(fa[x]);
}
void merge(int x,int y)
{
int xx=find(x),yy=find(y);
if(xx!=yy)
{
fa[xx]=yy,siz_e[yy]+=siz_e[xx],sizv[yy]+=sizv[xx];
}
}
int n,Q;
void solve()
{
cin>>n>>Q;
for(int i=1;i<=1000000;i++) fa[i]=i,sizv[i]=1;
for(int i=1;i<=n;i++) rel[i]=i;
int uidx=n;
while(Q--)
{
char op;
cin>>op;
if(op=='+')
{
int u,v;
cin>>u>>v;
merge(rel[u],rel[v]),siz_e[find(rel[u])]++;
}
else if(op=='-')
{
int u;
cin>>u;
siz_e[find(rel[u])]--,sizv[find(rel[u])]--;
rel[u]=++uidx;
}
else
{
int u;
cin>>u;
u=find(rel[u]);
if(siz_e[u]==0) cout<<"0";
else if(siz_e[u]==sizv[u]) cout<<"1";
else cout<<"?";
}
}
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
int _=1;
// cin>>_;
while(_--) solve();
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 | /* Things to notice: 1. do not calculate useless values 2. do not use similar names Things to check: 1. submit the correct file 2. time (it is log^2 or log) 3. memory 4. prove your naive thoughts 5. long long 6. corner case like n=0,1,inf or n=m 7. check if there is a mistake in the ds or other tools you use 8. fileio in some oi-contest 9. module on time 10. the number of a same divisor in a math problem 11. multi-information and queries for dp and ds problems */ #include<bits/stdc++.h> using namespace std; #define fi first #define se second #define pii pair<int,int> #define mp make_pair #define pb push_back const int mod=998244353; const int inf=0x3f3f3f3f; int fa[1000005],siz_e[1000005],sizv[1000005],rel[1000005]; int find(int x) { if(fa[x]==x) return x; return fa[x]=find(fa[x]); } void merge(int x,int y) { int xx=find(x),yy=find(y); if(xx!=yy) { fa[xx]=yy,siz_e[yy]+=siz_e[xx],sizv[yy]+=sizv[xx]; } } int n,Q; void solve() { cin>>n>>Q; for(int i=1;i<=1000000;i++) fa[i]=i,sizv[i]=1; for(int i=1;i<=n;i++) rel[i]=i; int uidx=n; while(Q--) { char op; cin>>op; if(op=='+') { int u,v; cin>>u>>v; merge(rel[u],rel[v]),siz_e[find(rel[u])]++; } else if(op=='-') { int u; cin>>u; siz_e[find(rel[u])]--,sizv[find(rel[u])]--; rel[u]=++uidx; } else { int u; cin>>u; u=find(rel[u]); if(siz_e[u]==0) cout<<"0"; else if(siz_e[u]==sizv[u]) cout<<"1"; else cout<<"?"; } } } signed main() { ios::sync_with_stdio(0); cin.tie(0); int _=1; // cin>>_; while(_--) solve(); return 0; } |
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