题意描述 Eqs 求一个五元方程 \(a_1x_1^3+a_2x_2^3+a_3x_3^3+a_4x_4^3+a_5x_5^3=0\) 的解的个数. 题中给出 \(a_i\) 的值并且保证 \(-50\leq a_i,x_i\leq 50,x_i\neq 0\).(\(1\leq i\leq 5\)) 算法分析 考虑暴力枚举,发现复杂度 \(100^5=10^{10}\),T 到飞起. 移项后变为:\(a_1x_1^3+a_2x_2^3+a_3x_3^3=-(a_4x_4^3+a_5x_5^3)…

一道典型的hash问题: 已知a1,a2,a3,a4,a5,求有多少种不同的<x1,x2,x3,x4,x5>组合满足等式: a1*x1^3 + a2*x2^3 + a3*x3^3 + a4*x4^3 + a5*x5^3 = 0 一种做法是暴力枚举,但因为xi∈[-50,-1)(1,50],所以暴力枚举时间为O(100^5),显然不可行. 所以只能用hash方法: 我们可以讲前两项 a1*x1^3 + a2*x2^3 的所有可能多项式结果SUM运算出来,并将这些SUM映射到hash表上.因为可能…

Description Consider equations having the following form: a1x13+ a2x23+ a3x33+ a4x43+ a5x53=0 The coefficients are given integers from the interval [-50,50]. It is consider a solution a system (x1, x2, x3, x4, x5) that verifies the equation, xi∈[-50,…

Eqs Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 15010   Accepted: 7366 Description Consider equations having the following form:  a1x13+ a2x23+ a3x33+ a4x43+ a5x53=0  The coefficients are given integers from the interval [-50,50].  I…

Eqs 题目链接:http://acm.hust.edu.cn/vjudge/problem/viewProblem.action?id=15029 题意: 给出系数a1,a2,a3,a4,a5,求出方程a1x1 3+ a2x2 3+ a3x3 3+ a4x4 3+ a5x5 3=0 有多少个解. 样例: Sample Input 37 29 41 43 47 Sample Output 654 分析: 如果直接用5个for循环是会超时的,所以把方程a1x1x1x1+a2x2x2x2+a3x3x…

POJ1840 问题重述: 给定系数a1,a2, ..,a5,求满足a1 * x1 ^ 3 + a2 * x2 ^ 3 +... + a5 * x5 ^ 3 = 0的 xi 的组数.其中ai, xi都在[-50, 50]内,且xi != 0. 算法: 1)用h[i]记录满足a1 *  x1 ^3 + a2 * x2 ^ 3 = i 的x1, x2组数. 2)令ans = 0, 循环x1, x2, x3的值,若 tmp = a3 * x3^3 + a4 * x4^3 + a5 * x5^3, h[…

Eqs Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 18299   Accepted: 8933 Description Consider equations having the following form: a1x13+ a2x23+ a3x33+ a4x43+ a5x53=0 The coefficients are given integers from the interval [-50,50]. It i…

C - Eqs Time Limit:5000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Submit Status Description Consider equations having the following form:  a1x1 3+ a2x2 3+ a3x3 3+ a4x4 3+ a5x5 3=0  The coefficients are given integers from the inter…

Eqs Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 15133   Accepted: 7426 Description Consider equations having the following form: a1x13+ a2x23+ a3x33+ a4x43+ a5x53=0 The coefficients are given integers from the interval [-50,50]. It i…

题目链接: https://vjudge.net/problem/POJ-1840 题目大意: 给出一个5元3次方程,输入其5个系数,求它的解的个数 其中系数 ai∈[-50,50]  自变量xi∈[-50,0)∪(0,50] 注意:xi不为0 解题思路: 五重循环肯定TLE,所以选择三重循环+两重循环,然后排序,二分找相同的数字即可 #include<iostream> #include<cstdio> #include<cstring> #include<st…