#include <bits/stdc++.h>
using namespace std;
const int N = 300'000 + 7;
const int Q = 1'000'000 + 7;
int n, q;
int cur[N];
int val[N + Q];
int uf[N + Q], sz[N + Q], cycle[N + Q];
int get(int u) {
return u == uf[u] ? u : uf[u] = get(uf[u]);
}
int main() {
ios::sync_with_stdio(false), cin.tie(nullptr);
for (int i = 0; i < N + Q; i++) {
uf[i] = i;
sz[i] = 1;
cycle[i] = 0;
}
cin >> n >> q;
for (int i = 1; i <= n; i++) {
val[i] = -1;
cur[i] = i;
}
int nxt = n + 1;
for (int rep = 0; rep < q; rep++) {
char op;
cin >> op;
if (op == '+') {
int a, b;
cin >> a >> b;
a = cur[a];
b = cur[b];
val[a] = 0;
val[b] = 0;
a = get(a);
b = get(b);
if (a == b) {
cycle[a] = +1;
}
else {
uf[b] = a;
sz[a] += sz[b];
if (cycle[a] == +1 || cycle[b] == +1) {
cycle[a] = +1;
}
}
}
else
if (op == '-') {
int c;
cin >> c;
int old = c;
c = cur[c];
sz[get(c)]--;
val[c] = +1;
c = old;
cur[c] = nxt++;
c = cur[c];
val[c] = -1;
}
else
if (op == '?') {
int d;
cin >> d;
d = cur[d];
if (cycle[get(d)] == +1 || val[d] == +1)
cout << '1';
else
if (val[d] == -1 || sz[get(d)] == 1)
cout << '0';
else
cout << '?';
}
else {
assert(false);
}
}
cout << '\n';
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 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 | #include <bits/stdc++.h> using namespace std; const int N = 300'000 + 7; const int Q = 1'000'000 + 7; int n, q; int cur[N]; int val[N + Q]; int uf[N + Q], sz[N + Q], cycle[N + Q]; int get(int u) { return u == uf[u] ? u : uf[u] = get(uf[u]); } int main() { ios::sync_with_stdio(false), cin.tie(nullptr); for (int i = 0; i < N + Q; i++) { uf[i] = i; sz[i] = 1; cycle[i] = 0; } cin >> n >> q; for (int i = 1; i <= n; i++) { val[i] = -1; cur[i] = i; } int nxt = n + 1; for (int rep = 0; rep < q; rep++) { char op; cin >> op; if (op == '+') { int a, b; cin >> a >> b; a = cur[a]; b = cur[b]; val[a] = 0; val[b] = 0; a = get(a); b = get(b); if (a == b) { cycle[a] = +1; } else { uf[b] = a; sz[a] += sz[b]; if (cycle[a] == +1 || cycle[b] == +1) { cycle[a] = +1; } } } else if (op == '-') { int c; cin >> c; int old = c; c = cur[c]; sz[get(c)]--; val[c] = +1; c = old; cur[c] = nxt++; c = cur[c]; val[c] = -1; } else if (op == '?') { int d; cin >> d; d = cur[d]; if (cycle[get(d)] == +1 || val[d] == +1) cout << '1'; else if (val[d] == -1 || sz[get(d)] == 1) cout << '0'; else cout << '?'; } else { assert(false); } } cout << '\n'; return 0; } |
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