import sys
readline=sys.stdin.readline

class Li_Chao_Tree:
    def __init__(self,N,X=None,inf=float("inf")):
        self.N=N
        if X==None:
            self.X=[x for x in range(self.N)]
        else:
            self.X=X
        self.idx={x:i for i,x in enumerate(self.X)}
        self.inf=inf
        self.li_chao_tree=[(0,self.inf)]*(2*self.N)
        self.left,self.right=[None]*2*N,[None]*2*N
        for i in range(self.N,2*self.N):
            self.left[i]=self.X[i-self.N]
            self.right[i]=self.X[i-self.N]
        for i in range(self.N-1,0,-1):
            self.left[i]=self.left[i<<1]
            self.right[i]=self.right[i<<1|1]

    def add_line_one_segment(self,a,b,i):
        queue=[i]
        while queue:
            i=queue.pop()
            aa,bb=self.li_chao_tree[i]
            l=a*self.X[self.left[i]]+b
            r=a*self.X[self.right[i]]+b
            ll=aa*self.X[self.left[i]]+bb
            rr=aa*self.X[self.right[i]]+bb
            if ll<=l and rr<=r:
                continue
            if l<=ll and r<=rr:
                self.li_chao_tree[i]=(a,b)
                continue
            queue.append(i<<1)
            queue.append(i<<1|1)

    def add_line(self,a,b,L=None,R=None):
        if L==None:
            L=self.N
        else:
            L+=self.N
        if R==None:
            R=2*self.N
        else:
            R+=self.N
        while L<R:
            if L%2:
                self.add_line_one_segment(a,b,L)
                L+=1
            if R%2:
                R-=1
                self.add_line_one_segment(a,b,R)
            L>>=1
            R>>=1

    def __call__(self,x):
        i=self.idx[x]+self.N
        retu=self.inf
        while i:
            a,b=self.li_chao_tree[i]
            retu=min(retu,a*x+b)
            i>>=1
        return retu
    
    def __getitem__(self,i):
        x=self.X[i]
        i+=self.N
        retu=self.inf
        while i:
            a,b=self.li_chao_tree[i]
            retu=min(retu,a*x+b)
            i>>=1
        return retu

    def __str__(self):
        li_chao_tree=[(0,inf)]*self.N
        for i,x in enumerate(self.X):
            ii=i+self.N
            while ii:
                aa,bb=self.li_chao_tree[ii]
                a,b=li_chao_tree[i]
                if aa*x+bb<a*x+b:
                    li_chao_tree[i]=aa,bb
                ii>>=1
        return "["+", ".join(map(str,li_chao_tree))+"]"

def Z_algorithm(lst):
    le=len(lst)
    LCP=[None]*le
    LCP[0]=le
    L,R=0,0
    for i in range(1,le):
        if i<R:
            x=LCP[i-L]
            if x<R-i:
                LCP[i]=x
            elif R-i<x:
                LCP[i]=R-i
            else:
                while R<le and lst[R-i]==lst[R]:
                    R+=1
                LCP[i]=R-i
                L=i
        else:
            R=max(R,i)
            while R<le and lst[R-i]==lst[R]:
                R+=1
            LCP[i]=R-i
            L=i
    return LCP

N,M=map(int,readline().split())
A=list(map(int,readline().split()))
B=list(map(int,readline().split()))
C=list(map(int,readline().split()))
Z=Z_algorithm(A+B)
inf=float("inf")
LCT=Li_Chao_Tree(M+1,inf=inf)
dp=[inf]*(M+1)
dp[0]=0
for m in range(M):
    k=Z[N+m]
    LCT.add_line(C[m],dp[m]-m*C[m],m,m+k+1)
    dp[m+1]=LCT[m+1]
if dp[M]==inf:
    ans=-1
else:
    ans=dp[M]
print(ans)