【链接】 我是链接,点我呀:)
【题意】

问你n!的b进制下末尾的0的个数

【题解】

证明:https://blog.csdn.net/qq_40679299/article/details/81167283
这题的话m比较大,
做个质因数分解就ok>_<
算n!有多少个x因子的话
以5为例子 (n=25)
25 20 15 10 5
把他们都除5
5 4 3 2 1
然后再除5
1
所以总共有6个
转换成代码就是
while(n>0){
ans+=n/5;
n = n/5;
}

【代码】

import java.io.*;
import java.util.*;public class Main {static int N = (int)1e6;static InputReader in;static PrintWriter out;public static void main(String[] args) throws IOException{//InputStream ins = new FileInputStream("E:\\rush.txt");InputStream ins = System.in;in = new InputReader(ins);out = new PrintWriter(System.out);//code start from herenew Task().solve(in, out);out.close();}static class Task{public void solve(InputReader in,PrintWriter out) {long n,m;n = in.nextLong();m = in.nextLong();ArrayList a = new ArrayList<>();ArrayList d = new ArrayList<>();for (long i = 2;i*i<=m;i++) {if (m%i==0) {a.add(i);int cnt1 = 0;while (m%i==0) {m/=i;cnt1++;}d.add(cnt1);}}if (m>1) {a.add(m);d.add(1);}long ans = (long)1e18 + 100;for (int i = 0;i <(int)a.size();i++) {long ai = (long) a.get(i);int pi = (int) d.get(i);long nn = n;long res = 0;while (nn>0) {res+=nn/ai;nn/=ai;}ans = Math.min(ans, res/pi);}out.print(ans);}}static class InputReader{public BufferedReader br;public StringTokenizer tokenizer;public InputReader(InputStream ins) {br = new BufferedReader(new InputStreamReader(ins));tokenizer = null;}public String next(){while (tokenizer==null || !tokenizer.hasMoreTokens()) {try {tokenizer = new StringTokenizer(br.readLine());}catch(IOException e) {throw new RuntimeException(e);}}return tokenizer.nextToken();}public long nextLong() {return Long.parseLong(next());}public int nextInt() {return Integer.parseInt(next());}}
}