program main
implicit None
integer(8)::d,g,i,s,n,j,k,ma
integer(8),allocatable::p(:),c(:),a(:),e(:)
character::b*10,f*1
	
	read*,d,g
	g = g/100
	allocate(p(d),c(d),a(d),e(d))
	do i = 1,d
		read *,p(i),c(i)
		c(i) = c(i)/100
		a(i) = i*p(i)+c(i)
	enddo
	
	k = sum(p)
	
	do i = 0,2**d-1
		write(b,"(b10.10)")i
		e =0
		do j = 11-d,10
			f = b(j:j)
			read(f,"(i1)")e(11-j)
		enddo
		s =0;n =0
		do j = 1,d
			s = s + a(j)*e(j)
			n = n + p(j)*e(j)
		enddo
		
		if(s >=g)then
			if(n < k) k = n
			cycle
		endif
		
		do j = d,1,-1
			if(e(j) == 0) exit
		enddo
		
		if(g-s <= j*p(j))then
			n = n + (g-s)/j
			if(mod(g-s,j)/=0) n = n+1
			if(n < k) k = n
		endif
	enddo
	
	print "(i0)",k
	
end program main