class segt:
    def __init__(self, n, calc):
        self.num = 2 ** (n - 1).bit_length()
        self.data = [[0] * 53 for _ in range(2 * self.num)]
        self.calc = calc

    def update(self, idx, x):
        idx += self.num - 1
        self.data[idx] = [0] * 53
        self.data[idx][x] = 1
        while idx > 0:
            idx = (idx - 1) >> 1
            self.data[idx] = self.calc(
                self.data[2 * idx + 1][:], self.data[2 * idx + 2][:]
            )[:]

    def renew(self, idx, x):
        self.update(idx, self.calc(self.get(idx), x))

    def prod(self, left, right):
        l = left + self.num
        r = right + self.num
        res_l = [0] * 53
        res_r = [0] * 53
        while l < r:
            if l % 2:
                res_l = self.calc(res_l[:], self.data[l - 1][:])[:]
                l += 1
            if r % 2:
                r -= 1
                res_r = self.calc(self.data[r - 1][:], res_r[:])[:]
            l >>= 1
            r >>= 1
        return self.calc(res_l, res_r)

    def get(self, idx):
        return self.data[idx + self.num - 1]


def func(x, y):

    res = [x[i] + y[i] for i in range(53)]
    s = sum(y[:26])

    for i in range(26):

        res[i + 26] += x[i] * (s - y[i])

    for i in range(26):

        res[52] += x[i] * (x[i] - 1) // 2 * (s - y[i])

        res[52] += x[i] * y[i + 26]
    return res


n = int(input())
s = list(map(lambda x: ord(x) - 65, input()))
st = segt(n, func)
for i in range(n):
    st.update(i, s[i])
for _ in range(int(input())):
    t, x, y = map(str, input().split())
    if t == "1":
        x = int(x) - 1
        y = ord(y) - 65
        st.update(x, y)
    else:
        l = int(x) - 1
        r = int(y)
        print(st.prod(l, r)[52])