题目大意:在4个都有n个元素的集合中,每个集合选出一个元素,使得4个数和为0.问有几种方案. 题目分析:二分.任选两组求和,剩下两组求和,枚举第一组中每一个和sum,在第二组和中查找-sum的个数,累加起来便得答案. 代码如下: # include<iostream> # include<cstdio> # include<vector> # include<cstring> # include<algorithm> using namespac…

用中途相遇法的思想来解题.分别枚举两边,和直接暴力枚举四个数组比可以降低时间复杂度. 这里用到一个很实用的技巧: 求长度为n的有序数组a中的数k的个数num? num=upper_bound(a,a+n,k)-lower_bound(a,a+n,k); #include<iostream> #include<cstdio> #include<cstdlib> #include<cstring> #include<cmath> #include&l…

Problem UVA1152-4 Values whose Sum is 0 Accept: 794  Submit: 10087Time Limit: 9000 mSec Problem Description The SUM problem can be formulated as follows: given four lists A,B,C,D of integer values, compute how many quadruplet (a,b,c,d) ∈ A×B×C×D are…

4 Values whose Sum is 0 题目链接:https://cn.vjudge.net/problem/UVA-1152 ——每天在线,欢迎留言谈论. 题目大意: 给定4个n(1<=n<=4000)元素的集合 A.B.C.D ,从4个集合中分别选取一个元素a, b,c,d.求满足 a+b+c+d=0的对数. 思路: 直接分别枚举 a,b,c,d ,坑定炸了.我们先枚举 a+b并储存,在B.C中枚举找出(-c-d)后进行比较即可. 亮点: 由于a+b,中会有值相等的不同组合,如果使…

传送门 4 Values whose Sum is 0 Time Limit: 15000MS   Memory Limit: 228000K Total Submissions: 20334   Accepted: 6100 Case Time Limit: 5000MS Description The SUM problem can be formulated as follows: given four lists A, B, C, D of integer values, compute…

4 Values whose Sum is 0 Time Limit: 15000MS   Memory Limit: 228000K Total Submissions: 13069   Accepted: 3669 Case Time Limit: 5000MS Description The SUM problem can be formulated as follows: given four lists A, B, C, D of integer values, compute how…

4 Values whose Sum is 0 Time Limit: 15000MS Memory Limit: 228000K Total Submissions: 17875 Accepted: 5255 Case Time Limit: 5000MS Description The SUM problem can be formulated as follows: given four lists A, B, C, D of integer values, compute how man…

4 Values whose Sum is 0 Time Limit: 15000MS Memory Limit: 228000K Total Submissions: 19322 Accepted: 5778 Case Time Limit: 5000MS Description The SUM problem can be formulated as follows: given four lists A, B, C, D of integer values, compute how man…

K - 4 Values whose Sum is 0 Crawling in process... Crawling failed Time Limit:9000MS     Memory Limit:0KB     64bit IO Format:%lld & %llu Submit Status Practice UVA 1152 Appoint description: System Crawler (2015-03-12) Description   The SUM problem c…

4 Values whose Sum is 0 Time Limit: 15000MS   Memory Limit: 228000K Total Submissions: 25615   Accepted: 7697 Case Time Limit: 5000MS Description The SUM problem can be formulated as follows: given four lists A, B, C, D of integer values, compute how…