【題解】ZeroJudge e973: 3. 滿意度調查 (Survey of Satisfaction)

N = list(input())
dic = {}
for c in N:
    dic[c] = dic.get(c, 0) + 1

for k, v in sorted(dic.items(), key=lambda x:(-x[1], x[0])):
    # 滿意度出現次數(dic.values())由高至低
    # 次數一樣則輸出滿意度值(dic.keys())小者
    print(f"{k} ", end="")
print()