KRUZNICE

문제

There are N circles on the coordinate axis defined by coordinate of the center C_i and radius R_i.

[이미지 1]

Write a program that will determine the smallest number of circles that have to be removed such that there is no intersecting pair of circles among the remaining circles. Remaining circles are allowed to touch at one point.

입력

The first line contains one integer N (1 ≤ N ≤ 1000), number of circles. 

The next N lines contain two integers each C_i and R_i (1 ≤ C_i, R_i ≤ 100), coordinate of the center and radius of each circle. Two circles with the same radius will always be centered at different coordinate. 

출력

Output one integer, the smallest number of circles that have to be removed such that no pair of remaining circles intersects. 

힌트

Clarification for the first sample: If we remove (5 1) and (1 2), the remaining circles do not intersect.