力扣-二维数组中的查找

剑指 Offer 04. 二维数组中的查找

1. 暴力输出

   /**
    * @param {number[][]} matrix
    * @param {number} target
    * @return {boolean}
    */
   var findNumberIn2DArray = function(matrix, target) {
       if (matrix[] == 0) return false;
       for ( var i = 0; i < matrix.length; i++) {
           for ( var j = 0; j < matrix[0].length; j++) {
               if ( matrix[i][j] == target ) {
                   return true;
               }
           }
       }
       return false;
   }
   

2. 利用二叉树

   /**
    * @param {number[][]} matrix
    * @param {number} target
    * @return {boolean}
    */
   var findNumberIn2DArray = function(matrix, target) {
       var i = matrix.length-1, j = 0;
       while ( i >= 0 && j < matrix[0].length ) {
           if ( matrix[i][j] > target ) i--;
           else if ( matrix[i][j] < target ) j++;
           else return true;
       }
       return false;
   }