http://codeforces.com/problemset/problem/807/C C. Success Rate time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are an experienced Codeforces user. Today you found out that during your…

题目链接:http://codeforces.com/contest/807/problem/C 题意:记 AC 率为当前 AC 提交的数量 x / 总提交量 y .已知最喜欢的 AC 率为 p/q (pq∈[0,1]) . 求最少在提交多少题(AC or NOT)能恰好达到 AC 率为 p/q 题解:当然可以用数学的方法来求解,我的解法并不是用什么数学方法,直接二分暴力就行. 由于(x+s)/(y+s+us)=(p/q)(s表示ac的,us表示没ac的)所以不妨设 x+s=k*p,y+s+us…

[题目链接]:http://codeforces.com/contest/807/problem/C [题意] 给你4个数字 x y p q 要求让你求最小的非负整数b; 使得 (x+a)/(y+b)==p/q 同时a为一个整数且0<=a<=b [题解] /* (x+a)/(y+b)==p/q; 则 x+a=np y+b=nq (以上结论只在p和q是互质的情况下有效,当然题目有说p和q互质) a=np-x b=nq-y a<=b 因为p<q所以n越大b会越大; 又p和q都大于等于0…

You are an experienced Codeforces user. Today you found out that during your activity on Codeforces you have made y submissions, out of which x have been successful. Thus, your current success rate on Codeforces is equal to x / y. Your favorite ratio…

C. Success Rate time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are an experienced Codeforces user. Today you found out that during your activity on Codeforces you have made ysubmissio…

Success Rate 思路: 水题: 代码: #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> using namespace std; #define ll long long inline void in(ll &now) { ; ') Cget=getchar(); ') { now=now*+Cget-'; Cget=getchar(…

C. Success Rate time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are an experienced Codeforces user. Today you found out that during your activity on Codeforces you have made y submissi…

Success Rate CodeForces - 807C 给你4个数字 x y p q ,要求让你求最小的非负整数b,使得 (x+a)/(y+b)==p/q,同时a为一个整数且0<=a<=b. (0 ≤ x ≤ y ≤ 109; 0 ≤ p ≤ q ≤ 109; y > 0; q > 0) 解法: (x+a)/(y+b)==p/q; --> x+a=np; y+b=nq; --> a=np-x; b=nq-y; --> 二分n; #include <cs…

Success Rate 题目链接 题意 给你两个分数形式的数,然后有两种变化方式 上下都+1 仅下面部分+1 让你求第一个分数变化到第二个分数的最小步数. 思路 有几种特殊情况分类讨论一下. 首先我们先把右边化为最简比. 我们可以得到方程$$\frac{(x+a)}{(y+b)} = \frac{kp}{kq}$$ \[a = k*p - x\\b = k*q - y \] 根据\(b >= a\)可求得\(k = \frac{y-x}{q-p}\)向上取整,并且要求a>=0: 代码 #in…

题目链接:http://codeforces.com/problemset/problem/807/C 题目大意:给你T组数据,每组有x,y,p,q四个数,x/y是你当前提交正确率,让你求出最少需要再提交几次可以达到目标正确率p/q; 解题思路:假设提交B次,正确A次,那么可以得到(x+A)/(y+B)=p/q,可以推出x+A=k*p,y+B=k*q.那么A=k*p-x,B=K*q-y; 这样我们只需要二分枚举k,判断A,B是否满足(0<=A<=B)即可. #include<iostre…