阿里笔试AK
第一题
水塔问题公式
在（n+1）/2上防水塔
import java.util.Arrays;
import java.util.Scanner;
/**
* Package: PACKAGE_NAME
* Created by OriKey on 2020/8/10.
* --- 平凡才是唯一的答案 ---
*/
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int n = in.nextInt();
long[]arr = new long[n];
for (int i = 0; i < n; i++) {
arr[i] = in.nextLong();
}
Arrays.sort(arr);
long sum = 0;
for (int i = 0; i < n; i++) {
sum+=Math.abs(arr[(n+1)/2-1]-arr[i]);
}
System.out.println(sum);
}
// public static void main(String[] args) {
// Scanner in = new Scanner(System.in);
//
// }s
第二题
求深度....肯定是比较浅的那个先赢。
#include <bits/stdc++.h> using namespace std; const int MAXN = 1e5 + 10; int n, m; vector<int> v[MAXN]; int dep[MAXN]; void dfs(int x) { for (auto y : v[x]) { dep[y] = dep[x] + 1; dfs(y); } } int main() { scanf("%d%d", &n, &m); for (int i = 2; i <= n; i++) { int x; scanf("%d", &x); v[x].push_back(i); } dfs(1); for (int i = 1; i <= m; i++) { int x, y; scanf("%d%d", &x, &y); if (dep[x] <= dep[y]) printf("A\n"); else printf("B\n"); } }