Description
Given a positive integer n, write a program to find out a nonzero multiple m of n whose decimal representation contains only the digits 0 and 1. You may assume that n is not greater than 200 and there is a corresponding m containing no more than 100 decimal
digits.
Input
The input file may contain multiple test cases. Each line contains a value of n (1 <= n <= 200). A line containing a zero terminates the input.
Output
For each value of n in the input print a line containing the corresponding value of m. The decimal representation of m must not contain more than 100 digits. If there are multiple solutions for a given value of n, any one of them is acceptable.
Sample Input
2 6 19 0
Sample Output
10 100100100100100100 111111111111111111
直接爆搜
#include<cstdio> #include<cstring> #include<cmath> #include<cstdlib> #include<iostream> #include<algorithm> #include<vector> #include<map> #include<queue> #include<stack> #include<string> #include<map> #include<set> #include<ctime> #define eps 1e-6 #define MAX 10005 #define INF 0x3f3f3f3f #define LL long long #define pii pair<int,int> #define rd(x) scanf("%d",&x) #define rd2(x,y) scanf("%d%d",&x,&y) #define rd3(x,y,z) scanf("%d%d%d",&x,&y,&z) ///map<int,int>mmap; ///map<int,int >::iterator it; using namespace std; bool found; void DFS(unsigned __int64 t,int n,int k) { if(found) return ; if(t%n==0) { printf("%I64u\n",t); found=true; return ; } if(k==19)//到第19层,回溯 return ; DFS(t*10,n,k+1); DFS(t*10+1,n,k+1); } int main() { int n; for(int i=1;i<200;i++) { found=false; DFS(1,i,0); //从1开始搜n的倍数,第三个参数代表搜的层数,当到第19层时返回(因为第20层64位整数存不下) } return 0; }