Mistake in my code?

#1

not passing all the testcases
question-wave print column wise
#include
using namespace std;
int main() {
int n,m;
cin>>n>>m;
int a[n][m];
for(int i=0;i<n;i++)
{
for(int j=0;j<m;j++)
cin>>a[i][j];
}
for(int i=0;i<n;i++)
{ if(i%2==0)
{
for(int j=0;j<m;j++)
cout<<a[j][i]<<", “;
}
else
{
for(int j=m-1;j>=0;j–)
cout<<a[j][i]<<”, ";
}
}
cout<<“END”;
return 0;
}

#2

Hi, refer this https://ide.codingblocks.com/s/630703

#3

Hi, i hope its clear now??

#4

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