Codeforces Round #644 (Div. 3) D. Buying Shovels

題目鏈接

題意：給你n,k。求k範圍內n的最大約數

思路：從1到$\sqrt{n}$枚舉他的約數，求最大。

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <set>
#include<iostream>
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define SIS std::ios::sync_with_stdio(false)
#define space putchar(' ')
#define enter putchar('\n')
typedef pair<int,int> PII;
const int mod=1e4+7;
const int N=2e6+10;
const int inf=0x7f7f7f7f;


ll gcd(ll a,ll b)
{
    return b==0?a:gcd(b,a%b);
}

ll lcm(ll a,ll b)
{
    return a*(b/gcd(a,b));
}

template <class T>
void read(T &x)
{
    char c;
    bool op = 0;
    while(c = getchar(), c < '0' || c > '9')
        if(c == '-')
            op = 1;
    x = c - '0';
    while(c = getchar(), c >= '0' && c <= '9')
        x = x * 10 + c - '0';
    if(op)
        x = -x;
}
template <class T>
void write(T x)
{
    if(x < 0)
        x = -x, putchar('-');
    if(x >= 10)
        write(x / 10);
    putchar('0' + x % 10);
}
int a[5000],b[5000];
int main()
{
    SIS;
    int t;
    cin>>t;
    while(t--)
    {
      ll  n,k;
      ll ans=inf;
      cin>>n>>k;
      for(int i=1;i*i<=n;i++)
      {
          if(n%i==0)
          {
              if(n/i<=k) ans=min(ans,n/(n/i));
              if(i<=k)ans=min(ans,n/i);
          }

      }
      cout<<ans<<endl;
    }

    return 0;
}