Problem D
Intervals
You are given n closed, integer intervals [ai,
bi] and n integers c1, ...,
cn.
Problem
Write a program that:
- reads the number of intervals, their end points
and integers c1, ..., cn from the
standard input,
- computes the minimal size of a set Z of integers which
has at least ci common elements with interval
[ai, bi], for each
i=1,2,...,n,
- writes the answer to the standard output.
Input
The first line of the input contains an integer n
(1 ≤ n ≤ 50000) -- the number of intervals. The
following n lines describe the intervals.
The (i+1)-th line of the input contains three integers
ai, bi and
ci separated by single spaces and such that
0 ≤ ai ≤ bi ≤ 50000 and
1 ≤ ci ≤ bi - ai+1.
Output
The output contains exactly one integer equal to the minimal size of
set Z sharing at least ci
elements with interval [ai, bi], for
each i=1,2,...,n.
Sample Input
5
3 7 3
8 10 3
6 8 1
1 3 1
10 11 1
Sample Output
6
ICPC/ACM Programming Contest - SWERC'2002 - University of Porto, Portugal