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treeguard 发表于 2016-12-4 15:58
可以hash 啊 对每一个单词 比如egg， e->1 g->2

这样会把不同的character hash 成一样的value? 目的是?

say543 发表于 2016-12-5 08:34
这样会把不同的character hash 成一样的value? 目的是?

回覆一下follow up, 有問題請指正:
Javascript:
// Given a string array, group the isomorphic strings into groups.
function isomorphicGroup(arr) {
  if (arr === null || arr.length === 0) return [];
  let result = [];

  // Use a helper method to build unique hash for different patterns
  function encoding(str) {
    let i = 0;
    let hash = "";
    let map = {};
    for(let c of str) {
      if (map[c] === undefined) {
        map[c] = i++;
        hash += map[c];
      }
    }
    return hash;
  }
  let isoMap = {};
  for (let str of arr) {
    // Unique pattern
    let hashStr = encoding(str);

    // Group the same pattern strings into same array.
    if (isoMap[hashStr] === undefined) {
      isoMap[hashStr] = [str];
    } else {
      isoMap[hashStr].push(str);
    }
  }
  // Build the result array
  for (let key in isoMap) {
    result.push(isoMap[key]);
  }
  return result;
}

let strArr = ['aba', 'zzz','dccb', 'ded', 'ccc', 'aaa', 'cbba'];
console.log(isomorphicGroup(strArr));
// [ [ 'zzz', 'ccc', 'aaa' ], [ 'aba', 'ded' ], [ 'dccb', 'cbba' ] ]