思路:对于c⋅lcm(a,b)−d⋅gcd(a,b)=x,由裴蜀定理可得想要使该式c,d为整数成立则x=k * gcd(gcd(a,b),lcm(a,b))=ngcd,所以第一个条件得出gcd的是x的因数。且c,d,x都已经明确给出,我们枚举每个x的因数作为gcd时会得出对应的lcm=(dgcd+x)/c,如果lcm不为整数排除。 那么现在我们已经花费...
Educational Codeforces Round 106 (Rated for Div. 2) D. The Number of Pairs 题意 给定三个正整数$c,d,x$,询问有多少对正整数对$(a,b)$,满足 \[ c \cdot lcm - d \cdot gcd = x \]
因为gcd()一定是x 的因子,则枚举x的每一个因子 埃氏筛预处理出2e7内每个数的质因子个数 constintMAX=2e7;intr[MAX+5];voidinit(){for(inti=2;i<=MAX;++i)//枚举每一个因数if(!r[i]){//保证只枚举质因数for(intj=i;j<=MAX;j+=i)r[j]++;//复杂度为(O nlogn);调和级数}}/*附加:预处...
For each test case, print one integer — the number of pairs(a,b)such that the above equality holds. 题解 昨晚的Educational Round,A题快速签到,B题离奇WA了4发才过后自闭了,瞄一眼C题太长了直接不想看,于是点开了D,简单数论: 设gcd(a,b)=t,a=ti,b=tj,则gcd(i,j)=1,代入题中等式: ...
Find the number of pairs of two-digit positive integers whose difference is equal to 50.▱▱-▱▱=50 ,请问满足条件的算式有多少个? A. 40 B.30 C. 50 D. 60 E. 10 相关知识点: 试题来源: 解析 [ Answer 】 A 【答案】 A▱▱-▱▱=50 6 0 small小 6 1 1 1 Large大 9...
[CF1499D]The Number of Pairs 数学 D. The Number of Pairs 题意 给你c,d,xc,d,x,求满足c⋅lcm(a,b)−d⋅gcd(a,b)=xc⋅lcm(a,b)−d⋅gcd(a,b)=x的点对(a,b)(a,b)的个数。 有TT组数据 T<=104T<=104,c,d,x<=107c,d,x<=107...
D. The Number of Pairs 数学 题目大意: 给你三个非零的三个整数 \(c、d、x\) ,你要求找一对 \((a,b)\) ,满足: \(c*lcm(a,b)-d*gcd(a,b)=x\) 。 题解: 比赛的时候没有推出了,哭了 令\(w = gcd(a,b),a*b = w^2*t\)...
3. Determine the number of pairs of integers (x:y) such that ( x,y):|x|+|y|20 . Where[r| is the absolute value function defined in question I above. D A. 400 B. 600 C. 661 D. 761 E. 790 相关知识点: 试题来源: 解析 DD When can be any integer between -19 and 19 ...
This is reminiscent of a corresponding formula of Gow and Waterhouse for single asymmetric bilinear forms.doi:10.1006/ffta.1997.0198G.D. WilliamsFinite Fields and Their ApplicationsG.D. Williams, The number of pairs of quadratic forms over Fq (q odd), Finite Fields Appl. 4 (1998) 38-42....
Step by step video & image solution for The sum of two numbers is 629 and their HCF is 37. The number of pairs satisfying the above condition is by Maths experts to help you in doubts & scoring excellent marks in Class 10 exams.Updated on:21/07/2023Class...