首先该游戏可以看作一个4*4的二维数组的更新游戏，玩家通过控制数组内元素的合并来不断产生更大的数字，当方向确定时，每一行或每一列的计算方式实际上是一样的，例如，当我确定方向为向左时，每一行的计算方式都是一样的，这样，我们就可以将二维数组的计算简化为一维数组的计算了，然后通过循环计算其他行即可。
var arr = [
[1, 1, 2, 2],
[1, 2, 2, 2],
[1, 0, 0, 2],
[1, 2, 2, 4],
]
console.log(get2048NewArray(arr, ))
console.log(get2048NewArray(arr, ‘left‘)) // [ [ 2, 4, 0, 0 ], [ 1, 4, 2, 0 ], [ 1, 2, 0, 0 ], [ 1, 4, 4, 0 ] ]
console.log(get2048NewArray(arr, ‘right‘)) // [ [ 0, 0, 2, 4 ], [ 0, 1, 2, 4 ], [ 0, 0, 1, 2 ], [ 0, 1, 4, 4 ] ]
console.log(get2048NewArray(arr, ‘up‘)) // [ [ 2, 2, 0, 0 ], [ 1, 4, 0, 0 ], [ 4, 2, 0, 0 ], [ 4, 2, 4, 0 ] ]
console.log(get2048NewArray(arr, ‘down‘)) // [ [ 0, 0, 2, 2 ], [ 0, 0, 1, 4 ], [ 0, 0, 2, 4 ], [ 0, 2, 4, 4 ] ]
function get2048NewArray(arr, direction) {
var arrT = arrayTransposition(arr)
var newArr = []
switch (direction) {
// 向上
case ‘up‘:
for (var i = 0; i < 4; i++) {
newArr[i] = mergeArrayElement(arrT[i])
}
break
// 向下
case ‘down‘:
for (var i = 0; i < 4; i++) {
newArr[i] = mergeArrayElement(arrT[i].reverse()).reverse()
}
break
// 向右
case ‘right‘:
for (var i = 0; i < 4; i++) {
// 为了不影响原数组，slice复制一下
newArr[i] = mergeArrayElement(arr[i].slice().reverse()).reverse()
}
break
case ‘left‘:
default:
// 向左
for (var i = 0; i < 4; i++) {
newArr[i] = mergeArrayElement(arr[i])
}
}
return newArr
// 一维数组合并相邻非空项
function mergeArrayElement(arr) {
var newArr = []
var index = -1 // index为-1表示未找到一个非空值
for (var i = 0; i < arr.length; i++) {
if (arr[i] != 0) {
if (index != -1) {
if (arr[index] == arr[i]) {
newArr.push(arr[index] * 2)
index = -1
} else {
newArr.push(arr[index])
index = i
}
} else {
index = i
}
}
}
if (index != -1) newArr.push(arr[index])
// 如果新数组长度不足4，补0
while (newArr.length < 4) {
newArr.push(0)
}
return newArr
}
// 二维数组转置
function arrayTransposition(arr) {
var newArr = [
[],
[],
[],
[]
]
for (var i = 0; i < arr.length; i++) {
for (var j = 0; j < arr[0].length; j++) {
newArr[i][j] = arr[j][i]
}
// console.log(newArr[0][0])
}
return newArr
}
}
var arr = [
[1, 1, 2, 2],
[1, 2, 2, 2],
[1, 0, 0, 2],
[1, 2, 2, 4],
]
console.log(get2048NewArray(arr, ))
console.log(get2048NewArray(arr, ‘left‘)) // [ [ 2, 4, 0, 0 ], [ 1, 4, 2, 0 ], [ 1, 2, 0, 0 ], [ 1, 4, 4, 0 ] ]
console.log(get2048NewArray(arr, ‘right‘)) // [ [ 0, 0, 2, 4 ], [ 0, 1, 2, 4 ], [ 0, 0, 1, 2 ], [ 0, 1, 4, 4 ] ]
console.log(get2048NewArray(arr, ‘up‘)) // [ [ 2, 2, 0, 0 ], [ 1, 4, 0, 0 ], [ 4, 2, 0, 0 ], [ 4, 2, 4, 0 ] ]
console.log(get2048NewArray(arr, ‘down‘)) // [ [ 0, 0, 2, 2 ], [ 0, 0, 1, 4 ], [ 0, 0, 2, 4 ], [ 0, 2, 4, 4 ] ]
function get2048NewArray(arr, direction) {
var arrT = arrayTransposition(arr)
var newArr = []
switch (direction) {
// 向上
case ‘up‘:
for (var i = 0; i < 4; i++) {
newArr[i] = mergeArrayElement(arrT[i])
}
break
// 向下
case ‘down‘:
for (var i = 0; i < 4; i++) {
newArr[i] = mergeArrayElement(arrT[i].reverse()).reverse()
}
break
// 向右
case ‘right‘:
for (var i = 0; i < 4; i++) {
// 为了不影响原数组，slice复制一下
newArr[i] = mergeArrayElement(arr[i].slice().reverse()).reverse()
}
break
case ‘left‘:
default:
// 向左
for (var i = 0; i < 4; i++) {
newArr[i] = mergeArrayElement(arr[i])
}
}
return newArr
// 一维数组合并相邻非空项
function mergeArrayElement(arr) {
var newArr = []
var index = -1 // index为-1表示未找到一个非空值
for (var i = 0; i < arr.length; i++) {
if (arr[i] != 0) {
if (index != -1) {
if (arr[index] == arr[i]) {
newArr.push(arr[index] * 2)
index = -1
} else {
newArr.push(arr[index])
index = i
}
} else {
index = i
}
}
}
if (index != -1) newArr.push(arr[index])
// 如果新数组长度不足4，补0
while (newArr.length < 4) {
newArr.push(0)
}
return newArr
}
// 二维数组转置
function arrayTransposition(arr) {
var newArr = [
[],
[],
[],
[]
]
for (var i = 0; i < arr.length; i++) {
for (var j = 0; j < arr[0].length; j++) {
newArr[i][j] = arr[j][i]
}
// console.log(newArr[0][0])
}
return newArr//.reverse()
}
}
