#include #include #include #include using namespace std; using ll=long long; using mint=atcoder::modint998244353; #define rep(i,n) for(int i=0;i<(n);i++) #define rrep(i,n) for(int i=(n)-1;i>=0;i--) #define all(v) v.begin(),v.end() #define rall(v) v.rbegin(),v.rend() template bool chmax(T &a, T b){if (a < b){a = b;return true;} else return false;} template bool chmin(T &a, T b){if (a > b){a = b;return true;} else return false;} const ll MOD=998244353; const int MAX=2e6+10; vectorfac(MAX),finv(MAX),inv(MAX); void set_fac(){ fac[0]=fac[1]=1; finv[0]=finv[1]=1; inv[1]=1; for (int i=2;i>N>>M; M=abs(M); ll p=1; mint ans=0,P4=mint(4).pow(N); while(p*p<=M){ if(M%p==0){ int q=M/p; if((p+q)%2==0){ ll x=abs((p+q)/2),y=abs((p-q)/2); if((x+y)%2==N%2){ for(int i=x;i<=N;i+=2){ int b=(i-x)/2,a=x+b; int j=N-i; int d=(j-y)/2,c=y+d; if(d>=0){ mint r=fac[N]*finv[a]*finv[b]*finv[c]*finv[d]; if(x==0&&y==0)ans+=r; else if(x==0||y==0)ans+=2*r; else ans+=4*r; } } } } } p++; } ans/=P4; cout<