题解

#include <bits/stdc++.h>
using namespace std;
long long a,b,n; 
int main()
{
    freopen("decimal.in","r",stdin);
    freopen("decimal.out","w",stdout);
    scanf("%lld%lld%lld",&a,&b,&n);
    for (long long i = 1; i <= n; i++) a %= b,a *= 10;
    a /= b;
    printf("%lld",a);
    fclose(stdin);
    fclose(stdout);
    return 0;
}

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