标签：eve back test als 数组 ++ diff else mon
/**
* 尝试获取arr子集 y 使 x=Σy
* @param {Array} arr
* @param {number} x
* @param {Array} res
*/
function tryVisit(arr, x, res) {
res = res || arr.map(m => { return { x: x - m, item: [m] } });
for (let ri = 0; ri < res.length; ri++) {
const rr = res[ri];
let toDel = true;
for (let i = 0; i < arr.length; i++) {
const item = arr[i];
if (contains(rr.item, item)) continue;
let diff = rr.x - item;
if (diff < 0) { }
else if (diff > 0) {
rr.item.push(item)
rr.x = diff;
}
else {
rr.item.push(item);
console.log(rr.item.join(‘,‘))
return rr.item;
}
toDel = false;
}
if (toDel) res[ri] = undefined;
else res[ri] = rr;
}
let toVisit = res.filter(m => m != undefined);
if (toVisit.length != 0) tryVisit(arr, 0, toVisit)
}
/**
* arr 中是否包含 tag
* @param {Array} arr
* @param {*} tag
*/
function contains(arr, tag) {
for (let j = 0; j < arr.length; j++) {
const r = arr[j];
if (r == tag) {
return true;
}
}
}
function main() {
let tag = [1, 2, 3, 4, 6, 10, 99, 23, 22, 30];
let v = 101;
//test
console.log(‘test:每种方法都测试一下‘);
tryVisit(tag, v) && tryVisit(tag.reverse(), v) && tryVisit(tag.sort((m,n) => m-n), v) && tryVisit(tag.sort((m,n) => n-m), v);
//正序倒序、乱序、默认排序 等 多种尝试 比如 如果目标数是偶数 就按照奇数偶数排序试一下
console.log(‘use:只取一个‘);
tag = [1, 2, 3, 4, 6, 10, 99, 23, 22, 30];
let res = tryVisit(tag, v) || tryVisit(tag.reverse(), v) || tryVisit(tag.sort((m,n) => m-n), v) || tryVisit(tag.sort((m,n) => n-m), v);
}
main();
理论上尝试次数越多函数失效的可能性越少，我列出了 排序不排序和他们的反转情况
/**
* 尝试获取arr子集 y 使 x=Σy
* @param {Array} arr
* @param {number} x
* @param {Array} res
*/
function tryVisit(arr, x, res) {
res = res || arr.map(m => { return { x: x - m, item: [m] } });
for (let ri = 0; ri < res.length; ri++) {
const rr = res[ri];
let toDel = true;
for (let i = 0; i < arr.length; i++) {
const item = arr[i];
if (contains(rr.item, item)) continue;
let diff = rr.x - item;
if (diff < 0) { }
else if (diff > 0) {
rr.item.push(item)
rr.x = diff;
}
else {
rr.item.push(item);
console.log(rr.item.join(‘,‘))
return rr.item;
}
toDel = false;
}
if (toDel) res[ri] = undefined;
else res[ri] = rr;
}
let toVisit = res.filter(m => m != undefined);
if (toVisit.length != 0) tryVisit(arr, 0, toVisit)
}
/**
* arr 中是否包含 tag
* @param {Array} arr
* @param {*} tag
*/
function contains(arr, tag) {
for (let j = 0; j < arr.length; j++) {
const r = arr[j];
if (r == tag) {
return true;
}
}
}
function main() {
let tag = [1, 2, 3, 4, 6, 10, 99, 23, 22, 30];
let v = 101;
//test
console.log(‘test:每种方法都测试一下‘);
tryVisit(tag, v) && tryVisit(tag.reverse(), v) && tryVisit(tag.sort((m,n) => m-n), v) && tryVisit(tag.sort((m,n) => n-m), v);
//正序倒序、乱序、默认排序 等 多种尝试 比如 如果目标数是偶数 就按照奇数偶数排序试一下
console.log(‘use:只取一个‘);
tag = [1, 2, 3, 4, 6, 10, 99, 23, 22, 30];
let res = tryVisit(tag, v) || tryVisit(tag.reverse(), v) || tryVisit(tag.sort((m,n) => m-n), v) || tryVisit(tag.sort((m,n) => n-m), v);
}
main();
从数组中取出n个不同的数组成子集 y 使 x = Σy
标签：eve back test als 数组 ++ diff else mon
原文地址：https://www.cnblogs.com/zhuwansu/p/12001037.html
