https://vjudge.net/problem/POJ-1047
题意:
给一个整数,它的长度为n,从1开始一直到n和该整数相乘,判断每次结果是否和原来的整数是循环的。
思路:
大整数的乘法。
1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 #include <algorithm> 5 #include <cmath> 6 #include<vector> 7 using namespace std; 8 9 char s[65]; 10 int num[65]; 11 int temp[65]; 12 int n; 13 14 bool cacl(int m) 15 { 16 int t = 0; 17 for (int i = 0; i < n; i++) 18 { 19 temp[i] = (num[i] * m + t) % 10; 20 t = (num[i] * m + t) / 10; 21 } 22 if (t>0) return false; 23 return true; 24 } 25 26 bool judge() 27 { 28 for (int i = 0; i<n; ++i) 29 { 30 int k = 0; 31 if (temp[i] == num[0]) 32 { 33 while (k<n &&num[++k] == temp[(i+k) % n]); 34 if (k == n) return 1; 35 } 36 } 37 return 0; 38 } 39 40 int main() 41 { 42 //freopen("D:\\txt.txt", "r", stdin); 43 while (gets(s)) 44 { 45 memset(num, 0, sizeof(num)); 46 n = strlen(s); 47 for (int i = n - 1; i >= 0; i--) 48 { 49 num[n - 1 - i] = s[i] - ‘0‘; 50 } 51 bool flag = false; 52 for (int i = 2; i <= n; i++) 53 { 54 if (cacl(i)) 55 { 56 if (!judge()) 57 { 58 printf("%s is not cyclic\n", s); 59 flag = true; 60 break; 61 } 62 } 63 else 64 { 65 printf("%s is not cyclic\n", s); 66 flag = true; 67 break; 68 } 69 } 70 if (!flag) 71 printf("%s is cyclic\n", s); 72 } 73 return 0; 74 }
时间: 2024-10-24 11:50:14