题意 给你长度为n四个数列,每个数列选一个数使总和为4,有多少种选法(不同选法仅当起码有一个元素的下标不同) 输入 第一行,n 下面n行,每行四个数,代表ai,bi,ci,di 输出 选法数量 样例输入 6 -45 22 42 -16 -41 -27 56 30 -36 53 -37 77 -36 30 -75 -46 26 -38 -10 62 -32 -54 -6 45 样例输出 5 分析 1.傻逼算法:四重枚举 O(n4) 2.优化一点的傻逼算法:三重枚举+一重二分O(n3logn) 3.…

4 Values whose Sum is 0 Time Limit: 15000MS   Memory Limit: 228000K Total Submissions: 25675   Accepted: 7722 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…

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 x B x C x D are such that a + b + c + d = 0 . In the following, we assume that all lists have the same size n .…

Description The SUM problem can be formulated . In the following, we assume that all lists have the same size n . Input The first line of the input file contains the size of the lists n (). We then have n lines containing four integer values (with ab…

2017-08-01 21:29:14 writer:pprp 参考:http://blog.csdn.net/piaocoder/article/details/45584763 算法分析:直接暴力复杂度过高,所以要用二分的方法,分成两半复杂度就会大大降低: 题目意思: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的个数 代码如下: //首先将前两列任意两项相加得到数组x,再将后两列任意两项相加取反得到…

4 Values whose Sum is 0 Time Limit: 15000MS   Memory Limit: 228000K Total Submissions: 23757   Accepted: 7192 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: 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…

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…