#include <iostream>
using namespace std;
int main() {
int arr[3][3]={{1,2,3},{4,5,6},{7,8,9}};
int row= sizeof(arr)/sizeof(arr[0]);
int col= sizeof(arr[0])/sizeof(arr[0][0]);
for(int i=0;i<row;i++){
if(i%2==0){
for(int j=0;j<col;j++){
cout<<arr[i][j]<<" ";
}
}else{
for(int j=col-1;j>=0;j--){
cout<<arr[i][j]<<" ";
}
}
cout<<endl;
}
}
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