#include<bits/stdc++.h>
using namespace std;
int main()
{
	int a,b,n;
	cin>>a>>b>>n;
	for(int i=1;i<=a;i++)
	{
		a=a%b;
		a=a*10;
		a/=b;
	}
	cout<<a;
}

$这题只需要重复执行除法运算的过程就好了，不算太难$

BUG：

$→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→→？$

提示按下鼠标滚轮，鼠标向右移有惊喜！！！

#include<stdio.h> 
using namespace std;
int t,a,b,n;
int main()
{
    scanf("%d%d%d",&a,&b,&n);
    for (int i = 1; i<=n; i++)
    {
        a*=10;
        t=a/b;
        a%=b;
    }
    printf("%d",t );
}

//***************************

//dev c++[[990.cpp]]*******

//dev c++[top fanil]]******

//dev c++*www.temege.com

#include <stdio.h>

#include <iostream>

#include <math.h>

#include <queue>

#include <stack>

#include <vector>

#include <iomanip>

using namespace std;

int main()

{

int a,b,n;





cin>>a>>b>>n;





a=a*10;





int ans;





while(n--)\






{





	ans=a/b;





	a%=b;





	a*=10;





}





cout<<ans<<endl;





return 0;

}

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#include <stdio.h>
#include <iostream>
#include <math.h>
using namespace std;
int main()
{
	long long a,b,n;
	cin>>a>>b>>n;
	while(n--)
	{
		a=a%b;
		a*=10;
	}
	cout<<a/b<<endl;
}