Submission #946745

#	Time	Username	Problem	Language	Result	Execution time	Memory
946745		PenguinsAreCute	Mutating DNA (IOI21_dna)	C++17	100 / 100	35 ms	7964 KiB

dna

#include <bits/stdc++.h>
using namespace std;
#define MAXN 121010
struct pref_sum {
	vector<int> v; int n;
	pref_sum(): n(MAXN) {v.resize(n+1,0);}
	void up(int x, int u) {v[x+1]=u;}
	void compile() {for(int i=0;++i<=n;) v[i]+=v[i-1];}
	int qry(int l, int r) {return v[r+1]-v[l];}
} pre[3][3];
void init(std::string a, std::string b) {
	int n = a.size();
	for(int i=-1;++i<n;) pre[a[i]%3][b[i]%3].up(i,1);
	for(int i=-1;++i<3;) for(int j=0;j<3;j++) pre[i][j].compile();
}
int get_distance(int x, int y) {
	int arr[3][3];
	for(int i=-1;++i<3;) for(int j=-1;++j<3;) arr[i][j]=pre[i][j].qry(x,y);
	for(int i=-1;++i<3;) {
		int cnt = 0;
		for(int j=-1;++j<3;) cnt+=arr[i][j]-arr[j][i];
		if(cnt) return -1;
	}
	return max(arr[0][1],arr[1][0])+max(arr[0][2],arr[2][0])+min(arr[1][2],arr[2][1]);
}

• Subtask 1: 21 / 21
• Subtask 2: 22 / 22
• Subtask 3: 13 / 13
• Subtask 4: 28 / 28
• Subtask 5: 16 / 16