判断数组中是否包含某个值这里有四种方法.用的测试数据: let arr=["a","b","c"]; let arr2={"a":"aaa","b":"bbb","c":"ccc"}; in判断是否在数组的key里in操作符针对的是key,而非value.而对于普通的一维数组来说,key是隐藏的.所以,对于判断某个数组中是否含有
const n = this.item.answerSelfId.length; let num = 0; for (let m = 0 ; m < n ; m++) { if ( !this.item.answerSelfId[m]) { // 当前数组为empty时 this.item.answerSelfId[m] = ''; }else { this.item.answerSelfId[m] = this.item.answerSelfId[m].trim();// 去掉当前数组空串 }
题目传送门:POJ 1269 Intersecting Lines Description We all know that a pair of distinct points on a plane defines a line and that a pair of lines on a plane will intersect in one of three ways: 1) no intersection because they are parallel, 2) intersect in
1. A & B,得到的结果C中的1的位表明了A和B中相同的位都是1的位:2. A | B, 得到的结果D中的1的位表明了A和B在该位至少有一个为1的位,包含了A 与 B 都是1的位数,经过前两步的位运算,,C 中1的位表明了A 和 B在该位都是1,D中为0的位表明了A 和 B 在该位都是0 ,所以进行第三步.3. C ^ D,E 中为1的位表明了A 和 B不同的位. #include<iostream> using namespace std; int getNum(int n) {
public class TEST { public static void main(String[] args) { int [] oldArr= {1,3,4,5,0,0,6,6,0,5,4,7,6,7,0,5}; int [] newArr= new int[oldArr.length] ; int n=0; for (int i=0;i<oldArr.length;i++) { if(oldArr[i]==0) {} else { newArr[n]=oldArr[i]; n++; }