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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#738458 | #9622. 有限小数 | qzhfx | TL | 0ms | 0kb | C++23 | 1.8kb | 2024-11-12 19:07:31 | 2024-11-12 19:07:34 |
answer
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e6 + 7;
const int mod = 998244353;
const int L = 1e9;
// #define ll __int128
//求解不定方程 ax+by=c 的最小整数解 x
ll exgcd(ll a, ll b, ll &x, ll &y)
{
if (!b) {x = 1; y = 0; return a;}
ll ans = exgcd(b, a % b, x, y);
ll tmp = x;
x = y;
y = tmp - a / b * y;
return ans;
}
ll x, y;
ll cal(ll a, ll b, ll c)
{
x = 0, y = 0;
ll ans = exgcd(a, b, x, y);
if (c % ans)return -1;
x *= c / ans; b /= ans;
// y *= c / ans;
if (b < 0)b = -b;
x = (x % b + b) % b;
return x;
}
std::vector<ll> px;
void solve()
{
int a, b;
cin >> a >> b;
ll p = b, k = 1;
while (p % 2 == 0) {
p /= 2;
k *= 2;
}
while (p % 5 == 0) {
p /= 5;
k *= 5;
}
long long c = 1e18, t = 0;
auto check = [&](ll id) {
c = cal(k, a, p * id);
// cerr << c << "\n";
t = (id*p - 1ll * k * c) / a;
return t >= 1;
};
ll d = 1;
ll cx = 1e18,ct = 0;
for(auto pd:px){
ll s = pd * k;
check(s);
if(c >=0&&cx > c){
cx = c;
d = pd;
}
}
cout << cx << " " << d << '\n';
}
int main()
{
ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
px.push_back(1);
for(int i=0;;i++){
ll now = 1;
int x = i;
while(x --){
now *= 2;
}
if(now > L)break;
for(int j=0;;j++){
int y = j;
while(y--){
now *= 5;
}
px.push_back(now);
}
}
int _ = 1;
cin >> _;
while (_--)
solve();
return 0;
}
Details
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Test #1:
score: 0
Time Limit Exceeded
input:
4 1 2 2 3 3 7 19 79