mirror of
https://git.sb/baoshuo/OI-codes.git
synced 2024-12-24 03:31:59 +00:00
202. 最幸运的数字
https://www.acwing.com/problem/content/submission/code_detail/13373247/
This commit is contained in:
parent
a804001bc5
commit
8f9c6e307f
54
AcWing/202/202.cpp
Normal file
54
AcWing/202/202.cpp
Normal file
@ -0,0 +1,54 @@
|
||||
#include <algorithm>
|
||||
#include <iostream>
|
||||
#include <limits>
|
||||
|
||||
using std::cin;
|
||||
using std::cout;
|
||||
const char endl = '\n';
|
||||
|
||||
int t;
|
||||
long long l;
|
||||
|
||||
long long euler(long long x) {
|
||||
long long r = x;
|
||||
for (long long i = 2; i * i <= x; i++) {
|
||||
if (x % i == 0) {
|
||||
r = r / i * (i - 1);
|
||||
while (x % i == 0) x /= i;
|
||||
}
|
||||
}
|
||||
if (x > 1) r = r / x * (x - 1);
|
||||
return r;
|
||||
}
|
||||
|
||||
long long binpow(__int128 a, long long b, long long m) {
|
||||
a %= m;
|
||||
__int128 res = 1;
|
||||
while (b > 0) {
|
||||
if (b & 1) res = res * a % m;
|
||||
a = a * a % m;
|
||||
b >>= 1;
|
||||
}
|
||||
return res;
|
||||
}
|
||||
|
||||
int main() {
|
||||
std::ios::sync_with_stdio(false);
|
||||
|
||||
while (cin >> l, l) {
|
||||
long long d = std::__gcd(l, 8ll);
|
||||
long long n = euler(9ll * l / d);
|
||||
long long ans = std::numeric_limits<long long>::max();
|
||||
|
||||
for (long long i = 1; i * i <= n; i++) {
|
||||
if (n % i == 0) {
|
||||
if (binpow(10, i, 9ll * l / d) == 1) ans = std::min(ans, i);
|
||||
if (binpow(10, n / i, 9ll * l / d) == 1) ans = std::min(ans, n / i);
|
||||
}
|
||||
}
|
||||
|
||||
cout << "Case " << ++t << ": " << (ans == std::numeric_limits<long long>::max() ? 0 : ans) << endl;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
BIN
AcWing/202/data/3.ans
(Stored with Git LFS)
Normal file
BIN
AcWing/202/data/3.ans
(Stored with Git LFS)
Normal file
Binary file not shown.
BIN
AcWing/202/data/3.in
(Stored with Git LFS)
Normal file
BIN
AcWing/202/data/3.in
(Stored with Git LFS)
Normal file
Binary file not shown.
Loading…
Reference in New Issue
Block a user