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const ll MOD = 998244353;
ll mul(ll x, ll y) { return x * y % MOD; }
ll qpow(ll x, ll y) {
ll z = 1;
while (y > 0) {
if (y & 1) z = mul(z, x);
x = mul(x, x);
y >>= 1;
}
return z;
} // 求x**y%MOD
// 注意:当MOD为质数时, (x/y)%MOD=(x*(y**(MOD-2)))%MOD,即y在模MOD意义下的逆元为b^{-1} \equiv b^{p-2} mod p
void solve() {
int n, q, x;
cin >> n >> q;
string s;
cin >> s;
ll tot = 0;
rep(i, 0, n - 1) tot += (s[i] == '1' ? 1 : -1);
rep(i, 0, q - 1) {
cin >> x;
x--;
tot -= (s[x] == '1' ? 2 : -2);
s[x] = (s[x] == '1' ? '0' : '1');
cout << (n <= 4 ? qpow((1 << (4 - n)), MOD - 2) * (tot * tot % MOD + n - 2 + MOD) % MOD
: qpow(2, n - 4) * (tot * tot % MOD + n - 2 + MOD) % MOD)
<< endl;
}
return;
}
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