#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int N;
cin >> N;
string SS, SK, SH;
cin >> SS >> SK >> SH;
string ans(N, 'a');
int scoreS = 0, scoreK = 0, scoreH = 0;
for (int i = 0; i < N; i++) {
// 세 명 답이 전부 같은 경우 → 모두 맞추면 동점 → 다른 글자 선택
if (SS[i] == SK[i] && SK[i] == SH[i]) {
char c = 'a';
if (c == SS[i]) c = (c == 'a' ? 'b' : 'a');
ans[i] = c; // 아무도 점수 없음
} else {
// 우선 숭돌이 답으로 선택
ans[i] = SS[i];
if (ans[i] == SS[i]) scoreS++;
if (ans[i] == SK[i]) scoreK++;
if (ans[i] == SH[i]) scoreH++;
}
}
// 만약 최종 점수가 조건을 만족 못 하면,
// 고돌이 점수를 일부러 올려주는 시도
if (!(scoreS > scoreK && scoreK > scoreH)) {
for (int i = 0; i < N; i++) {
// 현재 선택이 숭돌이 답인데, 고돌이 답과 다르면
if (ans[i] == SS[i] && SS[i] != SK[i]) {
// 숭돌이 점수 1 줄이고 고돌이 점수 1 늘려보기
ans[i] = SK[i];
scoreS--; scoreK++;
if (ans[i] == SH[i]) scoreH++;
if (scoreS > scoreK && scoreK > scoreH) break;
// 복원 (조건 안되면 다시 원래대로)
if (!(scoreS > scoreK && scoreK > scoreH)) {
if (ans[i] == SH[i]) scoreH--;
ans[i] = SS[i];
scoreS++; scoreK--;
}
}
}
}
if (scoreS > scoreK && scoreK > scoreH) {
cout << ans << "\n";
} else {
cout << -1 << "\n";
}
}
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