CF50E.Square Equation Roots
普及/提高-
通过率:0%
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
A schoolboy Petya studies square equations. The equations that are included in the school curriculum, usually look simple:
x2+2bx+c=0 where b , c are natural numbers.Petya noticed that some equations have two real roots, some of them have only one root and some equations don't have real roots at all. Moreover it turned out that several different square equations can have a common root.
Petya is interested in how many different real roots have all the equations of the type described above for all the possible pairs of numbers b and c such that 1<=b<=n , 1<=c<=m . Help Petya find that number.
输入格式
The single line contains two integers n and m . ( 1<=n,m<=5000000 ).
输出格式
Print a single number which is the number of real roots of the described set of equations.
输入输出样例
输入#1
3 3
输出#1
12
输入#2
1 2
输出#2
1
说明/提示
In the second test from the statement the following equations are analysed:
b=1 , c=1 : x2+2x+1=0 ; The root is x=−1
b=1 , c=2 : x2+2x+2=0 ; No roots
Overall there's one root
In the second test the following equations are analysed:
b=1 , c=1 : x2+2x+1=0 ; The root is x=−1
b=1 , c=2 : x2+2x+2=0 ; No roots
b=1 , c=3 : x2+2x+3=0 ; No roots
b=2 , c=1 : x2+4x+1=0 ; The roots are
b=2 , c=2 : x2+4x+2=0 ; The roots are
b=2 , c=3 : x2+4x+3=0 ; The roots are x1=−3,x2=−1
b=3 , c=1 : x2+6x+1=0 ; The roots are
b=3 , c=2 : x2+6x+2=0 ; The roots are
b=3 , c=3 : x2+6x+3=0 ; The roots are Overall there are 13 roots and as the root −1 is repeated twice, that means there are 12 different roots.