以下代码输出什么? import java.util.*;public class Test { public static void main(String[] args) { Set set = new HashSet(); set.add(new A()); set.add(new A()); set.add(new A()); set.add(new A()); System.out.println(set); }} class A { int r = 1; public String toString() { return r + ""; } public boolean equals(Object o) { return this.r == ((A)o).r; } public int hashCode() { return r; }}
选项:
A:[1];
B:[1, 1];
C:[1, 1, 1];
D:[1, 1, 1, 1]
发布时间:2024-03-31 20:53:20