C++代码

#include<bits/stdc++.h> 
using namespace std; 
typedef long long ll; 
const int MAX=10000005; 
ll dp[MAX]; 
int main() 
{ 
    ll n,x,y; 
    cin >> n >> x >> y; 
    dp[1]=x; 
    for(int i=2; i<=n; i++) 
        if(i%2) 
            dp[i]=min(dp[i-1]+x, dp[i/2+1]+x+y); 
        else 
            dp[i]=min(dp[i-1]+x,dp[i/2]+y); 

    cout << dp[n] << endl; 
    return 0; 
}