Lighting System Design

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll>PLL;
typedef pair<int, int>PII;
typedef pair<double, double>PDD;
#define I_int ll
inline ll read()
{
    ll x = 0, f = 1;
    char ch = getchar();
    while(ch < '0' || ch > '9')
    {
        if(ch == '-')f = -1;
        ch = getchar();
    }
    while(ch >= '0' && ch <= '9')
    {
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    return x * f;
}
#define read read()
#define closeSync ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define multiCase int T;cin>>T;for(int t=1;t<=T;t++)
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define repp(i,a,b) for(int i=(a);i<(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
#define perr(i,a,b) for(int i=(a);i>(b);i--)
ll ksm(ll a, ll b, ll p)
{
    ll res = 1;
    while(b)
    {
        if(b & 1)res = res * a % p;
        a = a * a % p;
        b >>= 1;
    }
    return res;
}
const int inf = 0x3f3f3f3f;
#define PI acos(-1)
const double eps = 1e-8;
const int maxn =1e3+7;
struct node{
    int v,k,c,l;
}a[maxn];
int n,dp[maxn],sum[maxn];
bool cmp(node a,node b){
    return a.v<b.v;
}
int main(){
	while(cin>>n){
        if(!n) break;
        rep(i,1,n) cin>>a[i].v>>a[i].k>>a[i].c>>a[i].l;
        sort(a+1,a+1+n,cmp);
        sum[0]=0;
        rep(i,1,n)
            sum[i]=sum[i-1]+a[i].l;
        memset(dp,0x3f,sizeof dp);
        dp[0]=0;
        for(int i=1;i<=n;i++){
            for(int j=0;j<=i;j++){
                dp[i]=min(dp[i],dp[j]+(sum[i]-sum[j])*a[i].c+a[i].k);
            }
        }
        cout<<dp[n]<<endl;
	}
	return 0;
}