Create G037-B.cpp

Author: tmwilliamlin168

AtCoder/G037-B.cpp

@@ -0,0 +1,29 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+const int mxN=1e5, M=998244353;
+int n, a[3*mxN], d[4];
+string s;
+map<char, int> mp{{'R', 0}, {'G', 1}, {'B', 2}};
+vector<int> v[3];
+long long ans=1;
+
+int main() {
+	ios::sync_with_stdio(0);
+	cin.tie(0);
+
+	cin >> n >> s;
+	for(int i=0; i<3*n; ++i)
+		v[mp[s[i]]].push_back(i);
+	for(int i=0; i<n; ++i) {
+		a[min({v[0][i], v[1][i], v[2][i]})]=-1;
+		a[max({v[0][i], v[1][i], v[2][i]})]=1;
+	}
+	d[0]=n;
+	for(int i=0; i<3*n; ++i) {
+		ans=ans*d[a[i]+1]%M;
+		--d[a[i]+1];
+		++d[a[i]+2];
+	}
+	cout << ans;
+}