ntt solutionary

At about on January 26, May 15, NTT was deployed in 14 prefectures in the East Japan region, all NTT flets optical fiber networks and IP Phones using optical fiber networks are suddenly unavailable. In Japan, where IP phones are widely used to replace traditional phones, this is a very serious accident. Nearly 3 million of network users and 0.6 million of IP phone users are affected. After urgent repairs by

combined number and the number. N, K, a [] Ideas:Consider it as a polynomial of 1000000 items. If a [] = x exists, the coefficient of X is 1, and then the polynomial is automatically multiplied K times. The part with the coefficient not 0 indicates that K numbers can exist, you can use FFT + quick power. To avoid precision errors, change non-zero values to 1 after each quick power to avoid errors after it becomes very large, complexity O (1000000 * log000000 * logk), which is a little large. T

(In fact, this article should be written as "debugging techniques with FFT discussion + code problem method", the language is not good to write articles on tricky qaq)There are suggestions to welcome, there are omissions Welcome to add!FFT (Fast Fourier transform)/ntt (number theory transformation) is a common and practical optimization of convolution operationsBut the FFT/NTT process is not as visually ref

Today's a question, bare ntt, but I will not, so White sent 50 points.So he came to learn about NTT.The surface is very simple, do not bother to post, that is not the point I want to say.The emphasis is on NTT, also called the Fast number theory transformation.In many problems, we may encounter the polynomial multiplication problem in the mode meaning, when the traditional fast Fourier transform may not sat

The principle of rapid number theory change (NTT) is actually the same principle as the fast Fourier transform. For the Fermat prime of a shape such as m= c*2^n+1, it is assumed that its original root is G. So deceive g^ (m-1) ==1 and just (m-1) can divide 2^n. So the NTT transform can be performed in the modulo p field. The rotation factor is g^ ((m-1)/n). The other principles are the same as the FFT princ

, K;7 inta[n+Ten], b[n+Ten], tmp[n+Ten], tmp2[n+Ten];8 intP =998244353, G =3, g[k+1], ng[k+Ten], inv[n+Ten], inv2;9 intPowintAintb) {intt=1; for(; b;b>>=1, A= (LL) a*a%p)if(b1) t= (ll) t*a%p;returnt;}Ten voidNTT (int*a,intNintt) { One for(intI=1, j=0; i1; i++){ A for(ints=n;j^=s>>=1,~js;); - if(ij) Swap (A[i], a[j]); - } the for(intD=0;(1){ - intm=11, _w=t==1?G[d]:ng[d]; - for(intI=0; i for(intw=1, j=0; j){ - inta=a[i+j+m],b=a[i+j],t= (

Pick http://blog.csdn.net/coldef/article/details/57908865 Last time to do a set of simulation game, which need to ask the natural number k power and, then I will only n^2 ... I remember N^2 has 20 points, Nlogn can burst to 90 points ...--鏼 鏼 鏼 2015 national team paper It's probably just this polynomial to get the inverse, find the generating function.This is O (NLOGN) O (n\log N), but the modulus of this problem is not the prime number that satisfies the requirements of

NTT can easily explode int First to find the original root of the program (it seems that the original root of the NTT are 3)Code #include NTT: (prime numbers are random, generally speaking, the original number of prime numbers is 3, but for the sake of insurance recommended to call a Huangen program) #include

The first time you cut NTT, feel that NTT is the model version of the FFT, specifically can see http://blog.csdn.net/acdreamers/article/details/39026505 speak very clearly And then the coefficients can be preprocessed out, the time can be reduced a lot, but I am the template for the brevity or in the thinking of coefficients. Said so much nonsense, the following we get to the point: the topic of the simples

I will NTT. It's fake. I will be polynomial to inverse. It's fake. I can count Sterling. It's fake. The official explanation is Cdq+ntt or polynomial inversion, but I'm not GG.Fortunately there is a kind of direct NTT, to kneel Orz ANS=∑I=0N∑J=0ISI,JX2JX (j!) Ans=\sum\limits_{i=0}^n\sum\limits_{j=0}^is_{i,j}\times2^j\times (j!)SI,J=1J!∑K=0J (−1) kckj (j−k) I s_

NTT Aw, it's simple. The FFT F-F-T FFT can be accelerated due to the good nature of having the primary n units root wn=e2πin w n = e 2πi n w_n=e^{\frac{2\pi i}{n}}. In the natural number field, modulo p p p, the WN w n w_n can be replaced with gp−1n g p−1 n G^{\frac{p-1}{n}}, G G g is the root of P p p, it can be found that those properties are similar. The inverse transformation also converts gp−1n g p−1 n G^{\frac{p-1}{n}} to g−p−1n g−p−1 n g^{-\f

},w{b,c,d},c1{a,a,a} W{a},w{b,c,d},c2{a,a,a} W{a},w{b,c,d},c3{a,a,a} W{b},w{a,c,d},c1{a,a,a} W{b},w{a,c,d},c2{a,a,a} W{b},w{a,c,d},c3{a,a,a} W{c},w{a,b,d},c1{a,a,a} W{c},w{a,b,d},c2{a,a,a} W{c},w{a,b,d},c3{a,a,a} W{d},w{a,b,c},c1{a,a,a} W{d},w{a,b,c},c2{a,a,a} W{d},w{a,b,c},c3{a,a,a} W{a,b},w{c,d},c1{a,a,a} W{a,b},w{c,d},c2{a,a,a} W{a,b},w{c,d},c3{a,a,a} W{a,c},w{b,d},c1{a,a,a} W{a,c},w{b,d},c2{a,a,a} W{a,c},w{b,d},c3{a,a,a} W{a,d},w{b,c},c1{a,a,a} W{a,d},w{b,c},c2{a,a,a} W{a,d},w{b,c},c3{a,a,a}

Ask how many binary trees make each of the point weights in the given set C and the weight values and An FS f_s represents the number of qualified two-forked trees with a total weight of s.So thereF0=1fs=∑w∈c∑ifixfs−w−i \begin{align} &f_0=1\\ &f_s=\

Topic Portal: https://www.luogu.org/problemnew/show/P4233 Topic Analysis: This problem is I play the game when I saw, but at that time did not want to come out, even some points are not bothered to write Qaq. Later I analyzed why I always can not

Problem Solving Ideas: Consider directly enumerating the edges of each point, and the other points in the graph are connected to each other directly, then push the formula straight: Ans=n∗2c2n−1∑i=0n−1cin−1ik ans=n*2^{c_{n-1}^2}\sum\limits_{i=0}^{n-

optimizations will be smooth and exciting. I started to explain to my wife how to link OMP and MPI with shoes. When I drank several packets of coffee during the day, I began to suffer from insomnia in the middle of the night. As the saying goes, we often see rivers and lakes drifting. How can we leave without a knife? How can we avoid wet shoes? OMP gave me another lesson when doing Ray and model triangle-by-triangle interaction. According to the previous experience, this code is very conservat

With the rapid development of mobile communication, it becomes more and more important to solve the problem of indoor cover and capacity, and the micro-cell base station becomes an important means to improve the indoor coverage effect and to increase the special area capacity. The importance of 3G indoor coverage Good network coverage, especially indoor coverage is the key to the success of 3G, NTT DoCoMo is a good example:

The "Wireless LAN Access Service" suddenly went viral overnight. This kind of service, also known as "Hot Spot", uses wireless LAN technologies such as IEEE802.11b and IEEE802.11a, which can be up to 11 Mbit/s (or up to 36 Mbit/s) at a low cost when going out) high-speed Internet access. At present, Japanese NTT communication and other companies are providing related services in terms of mobile Internet Service (MIS.

The wireless LAN Access Service is also called a "hot spot" object. As long as there is a wireless LAN access service, we can connect to the wireless network based on the existing wireless devices for network applications. For more information, see the following section. At present, Japanese NTT communication and other companies are providing related services in terms of mobile Internet service MIS. NTT Eas

following briefly introduces some common optical fiber connectors: (1) FC Optical Fiber Connector This connector was first developed by NTT in Japan. FC is the abbreviation of Ferrule Connector, indicating that the external reinforcing mode is a metal sleeve, and the fastening mode is a screw. The earliest, FC type connector, the ceramic pin is connected to the end of the Plane Contact Mode (FC ). This type of connector is simple in structure, easy t