Currently Tiny is learning Computational Geometry. When trying to solve a problem called "The Closest Pair Of Points In The Plane", he found that a code which gave a wrong time complexity got Accepted instead of Time Limit Exceeded.
The problem is the follows. Given $*n*$ points in the plane, find a pair of points between which the distance is minimized. Distance between $(*x*_{1}, *y*_{1})$ and $(*x*_{2}, *y*_{2})$ is
.
The pseudo code of the unexpected code is as follows:
input n
for i from 1 to n
input the i-th point's coordinates into p[i]
sort array p[] by increasing of x coordinate first and increasing of y coordinate second
d=INF //here INF is a number big enough
tot=0
for i from 1 to n
for j from (i+1) to n
++tot
if (p[j].x-p[i].x>=d) then break //notice that "break" is only to be
//out of the loop "for j"
d=min(d,distance(p[i],p[j]))
output d
Here, $*tot*$ can be regarded as the running time of the code. Due to the fact that a computer can only run a limited number of operations per second, $*tot*$ should not be more than $*k*$ in order not to get Time Limit Exceeded.
You are a great hacker. Would you please help Tiny generate a test data and let the code get Time Limit Exceeded?
Input
A single line which contains two space-separated integers $*n*$ and $*k*$ ($2 ≤ *n* ≤ 2000$, $1 ≤ *k* ≤ 10^{9}$).
Output
If there doesn't exist such a data which let the given code get TLE, print "no solution" (without quotes); else print $*n*$ lines, and the $*i*$-th line contains two integers $*x*_{*i*}, *y*_{*i*}$ $(|*x*_{*i*}|, |*y*_{*i*}| ≤ 10^{9})$ representing the coordinates of the $*i*$-th point.
The conditions below must be held:
- All the points must be distinct.
$|*x*_{*i*}|, |*y*_{*i*}| ≤ 10^{9}$.- After running the given code, the value of
$*tot*$should be larger than$*k*$.
样例
4 3
0 0
0 1
1 0
1 1
2 100
no solution
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