大佬帮我看看哪里错了？

我的代码：

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const int MOD=998244353;
static ll A[300005], g[300005];
int main(){
    int n;
    ll m,a;
    cin>>n>>m>>a;
    for(int i=0;i<n;i++) cin>>A[i];
    ll ans=0;
    if(a==0){
        ll S=0;
        for(int i=0;i<n;i++){
            g[i] = A[i] / m;
            S ^= g[i];
        }
        if(S != 0){
            for(int i=0;i<n;i++){
                ll gi = g[i];
                ll T = S ^ gi;
                if(gi > T){
                    ll k = gi - T;
                    if(k >= 1 && k * m <= A[i]){
                        ans++;
                        if(ans >= MOD) ans -= MOD;
                    }
                }
            }
        }
        cout << ans % MOD;
        return 0;
    }
    ll d = __gcd(a, m);
    ll a1 = a / d, m1 = m / d;
    if(a1 == 1){
        ll S2 = 0;
        for(int i=0;i<n;i++){
            ll v = A[i] / d;
            ll gi = (v >= 1 ? (v & 1LL) : 0LL);
            g[i] = gi;
            S2 ^= gi;
        }
        if(S2 != 0){
            for(int i=0;i<n;i++){
                ll gi = g[i];
                ll T = S2 ^ gi;
                ll v = A[i] / d;
                if(v < 1) continue;
                ll K = (v - 1) / m1;
                if(m1 % 2 == 0){
                    if(((v - 1) & 1LL) == T){
                        ll cnt = (K + 1) % MOD;
                        ans = (ans + cnt) % MOD;
                    }
                } else {
                    ll tot = K + 1;
                    ll need = ((v - 1) - T) & 1LL;
                    ll cnt = (tot + (1 - need)) / 2;
                    ans = (ans + cnt % MOD) % MOD;
                }
            }
        }
        cout << ans % MOD;
        return 0;
    }
    ll S3 = 0;
    for(int i=0;i<n;i++){
        g[i] = (A[i] / d) / m1;
        S3 ^= g[i];
    }
    if(S3 != 0){
        for(int i=0;i<n;i++){
            ll gi = g[i];
            ll T = S3 ^ gi;
            if(gi > T){
                ll k = gi - T;
                if(k >= 1 && k * m1 <= A[i] / d){
                    ans++;
                    if(ans >= MOD) ans -= MOD;
                }
            }
        }
    }
    cout << ans % MOD;
    return 0;
}

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测试点结果：