求$AC$ $code$

#include<bits/stdc++.h>
#define fastio ios::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL)
using namespace std;
typedef long long ll;
const int maxn=1e5+10;
ll sum;
int main()
{
	int x,y,n;
	cin>>x>>y>>n;
	if((x-1)*10<y-1)
		sum=n*(x-1);
	else sum=(n%10)*(x-1)+(n/10)*(y-1);
	cout<<sum;
	return 0;
}