Nanami likes playing games, and is also really good at it. This day she was playing a new game which involved operating a power plant. Nanami's job is to control the generators in the plant and produce maximum output.
There are n generators in the plant. Each generator should be set to a generating level. Generating level is an integer (possibly zero or negative), the generating level of the i-th generator should be between li and ri (both inclusive). The output of a generator can be calculated using a certain quadratic function f(x), where x is the generating level of the generator. Each generator has its own function, the function of the i-th generator is denoted as fi(x).
However, there are m further restrictions to the generators. Let the generating level of the i-th generator be xi. Each restriction is of the form xu≤xv+d, where u and v are IDs of two different generators and d is an integer.
Nanami found the game tedious but giving up is against her creed. So she decided to have a program written to calculate the answer for her (the maximum total output of generators). Somehow, this became your job.
Output
Print a single line containing a single integer − the maximum output of all the generators. It is guaranteed that there exists at least one valid configuration.
Note
In the first sample,
f1(x)=x,
f2(x)=x+1, and
f3(x)=x+2, so we are to maximize the sum of the generating levels. The restrictions are
x1≤x2,
x2≤x3, and
x3≤x1, which gives us
x1=x2=x3. The optimal configuration is
x1=x2=x3=2, which produces an output of 9.
In the second sample, restrictions are equal to
|xi-xi+1|≤3 for
1≤i<n. One of the optimal configurations is
x1=1,
x2=4,
x3=5,
x4=8 and
x5=7.