每日一题 2103. 环和杆 （简单）

简单题，直接统计就行

class Solution:
    def countPoints(self, rings: str) -> int:
        n = len(rings) // 2
        cnt = [[0, 0, 0] for _ in range(10)]
        for i in range(0, 2*n, 2):
            if rings[i] == "R":
                cnt[int(rings[i + 1])][0] = 1
            if rings[i] == "G":
                cnt[int(rings[i + 1])][1] = 1
            if rings[i] == "B":
                cnt[int(rings[i + 1])][2] = 1
        
        ans = 0
        for i in cnt:
            if sum(i) == 3:
                ans += 1
        return ans