Question

给出一个排序的整数数组，例如

a = [0,1,2,5,6,9];

我想确定像

这样的范围

[
    [0,1,2],
    [5,6],
    [9]
]

到目前为止，我已经尝试了一个双/三循环，但它嵌套到非常讨厌的代码。也许这个问题可以通过递归或其他智能技巧来解决？

<小时/> 附加示例：

输入

b = [0,1,5,6,7,9];

输出

[
    [0,1],
    [5,6,7],
    [9]
]

Answer 1

使用Array＃reduece迭代，每当最后一个数字不等于新数字-1时，添加另一个子数组。将当前数字添加到最后一个子数组：

const a = [0,1,2,5,6,9];

const result = a.reduce((r, n) => {
  const lastSubArray = r[r.length - 1];
  
  if(!lastSubArray || lastSubArray[lastSubArray.length - 1] !== n - 1) {
    r.push([]);
  } 
  
  r[r.length - 1].push(n);
  
  return r;  
}, []);

console.log(result);

Answer 2

像@OriDrori这样的Array.reduce已经做得很好。

另一个想法是使用简单的for循环和切片。

＆＃13;

function groupArray(a) {
  const ret = [];
  if (!a.length) return ret;
  let ixf = 0;
  for (let ixc = 1; ixc < a.length; ixc += 1) {
    if (a[ixc] !== a[ixc-1] + 1) {
      ret.push(a.slice(ixf, ixc));
      ixf = ixc;  
    }
  }
  ret.push(a.slice(ixf, a.length));
  return ret;
}

console.log(JSON.stringify(groupArray([0,1,2,5,6,9])));

＆＃13;

Answer 3

这就是我提出的：

const a = [0,1,2,5,6,9];

const solution = (arr, expected = 0, group = []) => 
    arr.reduce((acc, c, i) => 
        ((c === expected 
            ? (group.push(c), expected++)
            : (acc.push(group), group = [c], expected=++c)), 
          (i === arr.length-1 && acc.push(group)), 
          acc), []);

console.log(solution(a));

Answer 4

您可以使用普通的for循环并检查当前数字与先前数字之间的差异

var a = [0, 1, 2, 5, 6, 7, 9];
// this variable will contain arrays
let finalArray = [];
// Create a recursive function
function checkPrevNextNumRec(array) {
  let tempArr = [];
  // if the array contaon only 1 element then push it in finalArray and
  // return it
  if (array.length === 1) {
    finalArray.push(array);
    return
  }
  // otherside check the difference between current & previous number
  for (let i = 1; i < array.length; i++) {
    if (array[i] - array[i - 1] === 1) {
      // if current & previous number is 1,0 respectively 
      // then 0 will be pushed
      tempArr.push(array[i - 1]);
    } else {
      // if current & previous number is 5,2 respectively 
      // then 2 will be pushed
      tempArr.push(array[i - 1])
      // create a an array and recall the same function
      // example from [0, 1, 2, 5, 6, 9] after removing 0,1,2 it 
      // will create a new array [5,6,9]
      let newArr = array.splice(i);
      finalArray.push(tempArr);
      checkPrevNextNumRec(newArr)
    }
    // for last element if it is not consecutive of
    // previous number 
    if (i === array.length - 1) {
      tempArr.push(array[i]);
      finalArray.push(tempArr)
    }
  }

}
checkPrevNextNumRec(a)
console.log(finalArray)

Javascript将数组中的数字与一系列连续数字组合在一起

4 个答案: