[20250825] BOJ / P4 / 가희의 수열놀이 (Large) / 권혁준

Author: oncsr

khj20006/202508/25 BOJ P4 가희의 수열놀이 (Large).md

@@ -0,0 +1,47 @@
+```cpp
+#include <bits/stdc++.h>
+using namespace std;
+
+int Q, MOD;
+vector<int> pos[1000001]{};
+stack<int> st;
+set<int> s;
+
+int main(){
+	cin.tie(0)->sync_with_stdio(0);
+
+	cin>>Q>>MOD;
+	if(MOD > Q) {
+		for(int o,a;Q--;) {
+			cin>>o;
+			if(o == 1) cin>>a;
+			if(o == 3) cout<<"-1\n";
+		}
+		return 0;
+	}
+
+	for(int i=0,o,a;i<Q;i++) {
+		cin>>o;
+		if(o == 1) {
+			cin>>a;
+			a %= MOD;
+			if(!pos[a].empty()) s.erase(pos[a].back());
+			s.insert(st.size());
+			pos[a].push_back(st.size());
+			st.push(a);
+		}
+		else if(o == 2) {
+			if(st.empty()) continue;
+			a = st.top(); st.pop();
+			s.erase(pos[a].back());
+			pos[a].pop_back();
+			if(!pos[a].empty()) s.insert(pos[a].back());
+		}
+		else {
+			if(s.size() != MOD) cout<<"-1\n";
+			else cout<<st.size()-(*s.begin())<<'\n';
+		}
+	}
+
+}
+```