矩阵置零-中等
难度:中等
 
题目描述:
给定一个  m x n  的矩阵,如果一个元素为 0,则将其所在行和列的所有元素都设为 0。请使用**原地算法。
**示例:**
输入: [
  [1, 1, 1],
  [1, 0, 1],
  [1, 1, 1],
];
输出: [
  [1, 0, 1],
  [0, 0, 0],
  [1, 0, 1],
];
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解题思路: ```javascript var setZeroes = function(matrix) { var rows={} var column={} for(var i=0;i==0){ rows[i]=false column[j]=false } } for(var i=0;i==false)||(column[j]==false)) matrix[i][j]=0 } }; ```
常数空间复杂度
var setZeroes = function (matrix) {
  let rowLen = matrix.length;
  let colLen = matrix[0].length;
  for (let i = 0; i < rowLen; i++) {
    for (let j = 0; j < colLen; j++) {
      if (matrix[i][j] == 0) {
        for (let rowI = 0; rowI < rowLen; rowI++) {
          if (matrix[rowI][j] != 0) {
            matrix[rowI][j] = true;
          }
        }
        for (let colI = 0; colI < colLen; colI++) {
          if (matrix[i][colI] != 0) {
            matrix[i][colI] = true;
          }
        }
      }
    }
  }
  for (let i = 0; i < rowLen; i++) {
    for (let j = 0; j < colLen; j++) {
      if (typeof matrix[i][j] == "boolean") {
        matrix[i][j] = 0;
      }
    }
  }
  return matrix;
};
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巧设-0
var setZeroes = function (matrix) {
  let rowLen = matrix.length;
  let colLen = matrix[0].length;
  for (let i = 0; i < rowLen; i++) {
    for (let j = 0; j < colLen; j++) {
      if (matrix[i][j] == 0 && 1 / matrix[i][j] > 0) {
        for (let rowI = 0; rowI < rowLen; rowI++) {
          if (matrix[rowI][j] != 0) {
            matrix[rowI][j] = -0;
          }
        }
        for (let colI = 0; colI < colLen; colI++) {
          if (matrix[i][colI] != 0) {
            matrix[i][colI] = -0;
          }
        }
      }
    }
  }
  return matrix;
};
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