HDU5829 NTT

以下这份代码并没有过。但感觉没有问题。不是蜜汁WA就是蜜汁T。

 

 

  1 #include <cstdio>
  2 #include <iostream>
  3 #include <cstring>
  4 #include <algorithm>
  5 typedef long long ll;
  6 using namespace std;
  7 const int mod = 998244353;
  8 const int N = 262144, K = 17;
  9 int i;
 10 int P = 998244353, G = 3, g[K+1], ng[K+10], inv[N+10];
 11 ll A[N*2+10], B[N*2+10];
 12 ll pow(ll a, int n){
 13     ll ans = 1;
 14     while(n){
 15         if(n&1)
 16             ans = ans*a%P;
 17         a = a*a%P;
 18         n >>= 1;
 19     }
 20     return ans;
 21 }
 22 void NTT(ll*a,int n,int t){
 23     for(int i=1,j=0;i<n-1;i++){
 24         for(int s=n;j^=s>>=1,~j&s;);
 25         if(i<j)swap(a[i], a[j]);
 26     }
 27     for(int d=0;(1<<d)<n;d++){
 28         int m=1<<d,m2=m<<1;
 29         ll _w=pow(G, (P-1)>>(d+1));
 30         if(t != 1) _w = pow(_w, P-2);
 31         for(int i=0;i<n;i+=m2)for(ll w=1,j=0;j<m;j++){
 32             ll&A=a[i+j+m],&B=a[i+j],t=w*A%P;
 33             A=B-t;if(A<0)A+=P;
 34             B=B+t;if(B>=P)B-=P;
 35             w=w*_w%P;//////////////////////
 36         }
 37     }
 38     if(t==-1)for(int i=0,j=pow(n, P-2);i<n;i++)a[i]=a[i]*j%P;
 39 }
 40 
 41 /*****************另一份NTT模板
 42 void change (ll y[], int len) {
 43     for(int i = 1, j = len / 2; i < len - 1; i++) {
 44         if(i < j) swap(y[i], y[j]);
 45         int k = len / 2;
 46         while(j >= k) {
 47             j -= k;
 48             k /= 2;
 49         }
 50         if(j < k) j += k;
 51     }
 52 }
 53 void ntt(ll y[], int len, int on) {
 54     change (y, len);
 55     for(int h = 2; h <= len; h <<= 1) {
 56         ll wn = pow(G, (mod-1)/h);
 57         if(on == -1) wn = pow(wn, mod-2);
 58         for(int j = 0; j < len; j += h) {
 59             long long w = 1;
 60             for(int k = j; k < j + h / 2; k++) {
 61                 long long u = y[k];
 62                 long long t = w * y[k + h / 2] % mod;
 63                 y[k] = (u + t) % mod;
 64                 y[k+h/2] = (u - t + mod) % mod;
 65                 w = w * wn % mod;
 66             }
 67         }
 68     }
 69     if(on == -1) {
 70         long long t = pow (len, mod - 2);
 71         for(int i = 0; i < len; i++)
 72             y[i] = y[i] * t % mod;
 73     }
 74 }
 75 ***************************/
 76 
 77 int a[N];
 78 int pow2[N], r[N], f[N], F[N];
 79 
 80 int main(){
 81 //    freopen("in", "r", stdin);
 82 //    freopen("outd", "w", stdout);
 83 //    for(g[K]=pow(G,(P-1)/N),ng[K]=pow(g[K],P-2),i=K-1;~i;i--)
 84 //        g[i]=(ll)g[i+1]*g[i+1]%P, ng[i]=(ll)ng[i+1]*ng[i+1]%P;
 85     for(inv[1]=inv[0]=1,i=2;i<N;i++) inv[i]=(ll)(P-inv[P%i])*(P/i)%P;
 86 
 87     for(f[0]=f[1]=r[0]=r[1]=pow2[0]=1, i=pow2[1]=2; i < N; i++){
 88         r[i] = (ll)inv[i]*r[i-1]%P;
 89         f[i] = (ll)i*f[i-1]%P;
 90         pow2[i] = (pow2[i-1]<<1)%P;
 91     }
 92 
 93     int t, ca = 1, n; scanf("%d", &t);
 94     while(t--){
 95         scanf("%d", &n);
 96         for(i = 1; i <= n; i++) scanf("%d", a+i);
 97         sort(a+1, a+n+1, greater<int>() );
 98 
 99         memset(B, 0, sizeof(B));
100         memset(A, 0, sizeof(A));
101         for(i = 1; i <= n; i++){
102             B[i-1] = (ll)f[i-1]*pow2[n-i]%P*a[i]%P;
103             A[i-1] = r[n-i];
104         }
105 
106         int len = 1;
107         while(len <= n+n) len <<= 1;
108         NTT(B, len, 1), NTT(A, len, 1);
109         for(int i = 0; i < len; i++)
110             A[i] = B[i]*A[i]%P;
111         NTT(A, len, -1);
112 
113         for(int i = 1; i <= n; i++){
114             F[i] = A[n-2+i]*(ll)r[i-1]%P+F[i-1];
115             if(F[i] >= P) F[i] %= P;
116             printf("%d ", F[i]);
117         }
118         puts("");
119     }
120     return 0;
121 }
View Code

 以上代码蜜汁T，NTT()换成ntt()后蜜汁WA。

和AC代码对拍很久也没看出什么问题。

posted @ 2016-10-10 23:10  我在地狱  阅读(296)  评论(0)  编辑  收藏  举报