P5723 完整代码
def is_prime(y):if y < 2:return Falsefor i in range(2, int(y**0.5) 1):if y % i 0:return Falsereturn Truen int(input())
sum_primes 0
x 0if n < 2:print("0")
elif n 2:print("2\n1")
else:for i in range(2, n 1):i…
题目: 题解:
class Solution {public int fourSumCount(int[] A, int[] B, int[] C, int[] D) {Map<Integer, Integer> countAB new HashMap<Integer, Integer>();for (int u : A) {for (int v : B) {countAB.put(u v, countAB.getOrDefa…