传送门 题目大意:n个二元组a[i],b[i],去掉k个,求sigma a[i]/ sigma b[i]的最大值 代码: #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define N 1009 #define LL long long using namespace std; LL n,k; LL a[N],b[N]; double c[N]; inli…

传送门 01分数规划板子题啊. 就是简单变形移项就行了. 显然 ∑i=1na[i]∑i=1nb[i]≤k" role="presentation" style="position: relative;">∑ni=1a[i]∑ni=1b[i]≤k∑i=1na[i]∑i=1nb[i]≤k 于是我们二分k. 只需检验: ∑i=1n(a[i]−b[i]∗k)≤0" role="presentation" style="…

Dropping tests Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 8176   Accepted: 2862 Description In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be . Given…

Dropping tests   Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 6373   Accepted: 2198 [Description] In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be . G…

Dropping tests Time Limit: 1000MS   Memory Limit: 65536K Total Submissions:17069   Accepted: 5925 Description In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be . Given…

POJ - 2976 Dropping tests 你有 \(n\) 次考试成绩, 定义考试平均成绩为 \[\frac{\sum_{i = 1}^{n} a_{i}}{\sum_{i = 1}^{n} b_{i}}\] 你可以考虑放弃 \(K\) 次成绩, 求最大平均成绩 * 100 小插曲: 被精度卡成喜羊羊 0/1分数规划\(from\)人生导师 Solution 01分数规划(不是很)裸题, 在每次 \(check\) 时, 选取较大的 \(num - K + 1\) 次即可 Code #…

[POJ2976]Dropping Tests(分数规划) 题面 Vjudge 翻译在\(Vjudge\)上有(而且很皮) 题解 简单的\(01\)分数规划 需要我们做的是最大化\(\frac{\sum a[i]}{\sum b[i]}\) 考虑二分答案 将最大化问题转换为判定问题 \(\sum{a[i]}-mid\sum{b[i]}\geq 0\) 因为所有选定的\(i\)是一样的 所以可以将权值化为\(a[i]-mid·b[i]\),这样只需要贪心的选择最大的那部分检查是否大于零就行了 #i…

Dropping tests Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 11367   Accepted: 3962 Description In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be . Give…

In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be . Given your test scores and a positive integer k, determine how high you can make your cumulative average if you are…

Dropping tests Time Limit: 1000MS Memory Limit: 65536K Description In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be Given your test scores and a positive integer k, d…