1+ /**
2+ * Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.
3+ *
4+ * Follow up:
5+ *
6+ * Did you use extra space?
7+ * A straight forward solution using O(mn) space is probably a bad idea.
8+ * A simple improvement uses O(m + n) space, but still not the best solution.
9+ * Could you devise a constant space solution?
10+ *
11+ * res.js
12+ * @authors Joe Jiang (hijiangtao@gmail.com)
13+ * @date 2017年02月28日 13:49:19
14+ * @version $Id$
15+ *
16+ * @param {number[][] } matrix
17+ * @return {void } Do not return anything, modify matrix in-place instead.
18+ */
19+ let setZeroes = function ( matrix ) {
20+ if ( ! matrix . length ) {
21+ return ;
22+ }
23+ 24+ let rowlen = matrix . length ,
25+ collen = matrix [ 0 ] . length ,
26+ rowzero = false ,
27+ colzero = false ;
28+ 29+ for ( let i = 0 ; i < rowlen ; i ++ ) {
30+ for ( let j = 0 ; j < collen ; j ++ ) {
31+ if ( matrix [ i ] [ j ] === 0 ) {
32+ matrix [ i ] [ 0 ] = 0 ;
33+ matrix [ 0 ] [ j ] = 0 ;
34+ 35+ if ( i === 0 ) {
36+ rowzero = true ;
37+ }
38+ if ( j === 0 ) {
39+ colzero = true ;
40+ }
41+ }
42+ }
43+ }
44+ 45+ for ( let i = 1 ; i < rowlen ; i ++ ) {
46+ for ( let j = 1 ; j < collen ; j ++ ) {
47+ if ( matrix [ i ] [ 0 ] === 0 || matrix [ 0 ] [ j ] === 0 ) {
48+ matrix [ i ] [ j ] = 0 ;
49+ }
50+ }
51+ }
52+ 53+ if ( rowzero ) {
54+ for ( let i = 0 ; i < collen ; i ++ ) {
55+ matrix [ 0 ] [ i ] = 0 ;
56+ }
57+ }
58+ if ( colzero ) {
59+ for ( let i = 0 ; i < rowlen ; i ++ ) {
60+ matrix [ i ] [ 0 ] = 0 ;
61+ }
62+ }
63+ } ;
64+ 65+ // Another solution
66+ let setZeroes = function ( matrix ) {
67+ if ( ! matrix . length ) {
68+ return ;
69+ }
70+ 71+ let rowlen = matrix . length ,
72+ collen = matrix [ 0 ] . length ,
73+ colzero = false ;
74+ 75+ for ( let i = 0 ; i < rowlen ; i ++ ) {
76+ if ( matrix [ i ] [ 0 ] === 0 ) {
77+ colzero = true ;
78+ }
79+ for ( let j = 1 ; j < collen ; j ++ ) {
80+ if ( matrix [ i ] [ j ] === 0 ) {
81+ matrix [ i ] [ 0 ] = 0 ;
82+ matrix [ 0 ] [ j ] = 0 ;
83+ }
84+ }
85+ }
86+ 87+ for ( let i = rowlen - 1 ; i >= 0 ; i -- ) {
88+ for ( let j = collen - 1 ; j >= 1 ; j -- ) {
89+ if ( matrix [ i ] [ 0 ] === 0 || matrix [ 0 ] [ j ] === 0 ) {
90+ matrix [ i ] [ j ] = 0 ;
91+ }
92+ }
93+ 94+ if ( colzero ) {
95+ matrix [ i ] [ 0 ] = 0 ;
96+ }
97+ }
98+ } ;
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