cp/kattis/18-2-2025/j.py

17 lines
353 B
Python

s = input()
n = len(s)
last_occurrence = {}
total = 0
for right in range(n):
char = s[right]
left = last_occurrence.get(char, -1) + 1
unique_chars = set()
for l in range(right - 1, left - 1, -1):
if s[l] not in unique_chars:
total += 1
unique_chars.add(s[l])
last_occurrence[char] = right
print(total)