AtCoder Beginner Contest 260 不参戦記 - Qiita

S = input() d = {} for c in S: d.setdefault(c, 0) d[c] += 1 for c in d: if d[c] == 1: print(c) exit() else: print(-1) N, X, Y, Z = map(int, input().split()) A = list(map(int, input().split())) B = list(map(int, input().split())) result = [] a = list(range(1, N + 1)) a.sort(key=lambda x: (A[x - 1], -x), reverse=True) result.extend(a[:X]) a = a[X:] a.sort(key=lambda x: (B[x - 1], -x), reverse=True)