框架:Java
public static List<Integer> buttonIdList = new ArrayList();
public void myMainMethod() {
for(Integer i = 0; i < 11; i++) {
int randomButtonId = getUniqueIdNumber();
}
}
private static Integer getUniqueIdNumber() {
Random ran = new Random();
int randomButtonId = ran.nextInt(20) + 1;
if(buttonIdList.contains(randomButtonId)) {
getUniqueIdNumber();
} else {
buttonIdList.add(randomButtonId);
}
return randomButtonId;
}
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当代码遇到重复时,它会自动调用(递归),在第二次尝试时,如果数字是唯一的,则return语句将其返回给myMainMethod或getUniqueIdNUmber?
退货声明应该放在哪里?
这是代码:
#include <cmath>
#include <iostream>
#include <iomanip>
#include <vector>
#include <cstdio>
int main(int argc, char *argv[]) {
const unsigned int max_chars = 100;
char buffer[max_chars];
std::cin.getline(buffer, max_chars, '\n');
unsigned int count = 0;
for (auto c : buffer) {
if (c == '\0') {
break;
}
count++;
}
std::cout << "Input: ===========" << std::endl;
std::cout << buffer << std::endl;
std::cout << "Number of chars ==" << std::endl;
std::cout << std::dec << count << std::endl;
std::cout << "==================" << std::endl;
} …Run Code Online (Sandbox Code Playgroud) List<Number> list = new ArrayList<Integer>();
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我正在尝试创建这个对象,但出现编译器错误,但我没有意义,因为 Integer 扩展了 Number,所以它应该可以工作。
我通过插入mySql数据库中的用户表创建了一个新用户 - 但它显示错误,说没有这样的列标题为"密码".哪个列负责mySql数据库中用户表中的密码?
mysql> INSERT INTO user
(host, user, password,
select_priv, insert_priv, update_priv)
VALUES ('localhost', 'guest',
PASSWORD('guest123'), 'Y', 'Y', 'Y');
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