Approach : Transpose and then reverse1
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27class Solution {
private void swap(int[][] arr,int i,int j){
int tmp=arr[i][j];
arr[i][j]=arr[j][i];
arr[j][i]=tmp;
}
private void transpose(int[][] matrix){
for(int i=0;i<matrix.length;i++){
for(int j=i;j<matrix[0].length;j++){
swap(matrix,i,j);
}
}
}
private void reverseRows(int[][] arr){
for(int[] row:arr){
int l=0,r=arr.length-1;
while(l<r){
int tmp=row[l];row[l]=row[r];row[r]=tmp;
l++;r--;
}
}
}
public void rotate(int[][] matrix) {
transpose(matrix);
reverseRows(matrix);
}
}