Set Matrix Zeroes

Set Matrix Zeroes

Problem:

Given a m x n Matrix, if an element was 0, set its entire row and column to 0. Do it on place.

Ideas:

Marking with a tag array

My Code:

 Public classSolution { Public voidSetzeroes (int[] matrix) {        if(Matrix = =NULL|| Matrix.length = = 0 | | Matrix[0].length = = 0)return; intm =matrix.length; intn = matrix[0].length; int[] row =New int[M]; int[] col =New int[n];  for(inti = 0; I < m; i++)        {             for(intj = 0; J < N; J + +)            {                if(Matrix[i][j] = = 0) {Row[i]= 1; COL[J]= 1; }            }        }                 for(inti = 0; I < m; i++)        {             for(intj = 0; J < N; J + +)            {                if(Row[i] = = 1 | | col[j] = = 1) {Matrix[i][j]= 0; }            }        }        return; }}

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Others code:

 Public classSolution {//using O (m+n) is easy and to enable O (1), we have the space within the matrix     Public voidSetzeroes (int[] matrix) {        if(Matrix = =NULL|| Matrix.length = = 0)            return; introws =matrix.length; intcols = matrix[0].length; BooleanEmpty_row0 =false; BooleanEmpty_col0 =false;  for(inti = 0; i < cols; i++){            if(Matrix[0][i] = = 0) {empty_row0=true;  Break; }        }                 for(inti = 0; i < rows; i++){            if(matrix[i][0] = = 0) {empty_col0=true;  Break; }        }                 for(inti = 1; i < rows; i++) {             for(intj = 1; j<cols; J + +){                if(Matrix[i][j] = = 0) {matrix[0][J] = 0; matrix[i][0] = 0; }            }        }                 for(inti = 1; i<rows; i++) {             for(intJ=1; j< cols; J + +) {                if(Matrix[0][j] = = 0 | | matrix[i][0] = = 0) Matrix[i][j]= 0; }        }              if(empty_row0) { for(inti = 0; i < cols; i++) {matrix[0][i] = 0; }                   }                if(empty_col0) { for(inti = 0; i < rows; i++) {matrix[i][0] = 0; }                   }    }}

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The Learning Place:

• The problem itself is characterized by using a tag array to mark which row and column have zero
• My code uses an extra space O (m+n), while others ' code hides the tags in their own people, typically in the possession of people, thus saving space.
• It seems to reduce the complexity of space: 1, increase the time complexity of multiple cycles 2, with their own space for storage, hidden in their own

Set Matrix Zeroes