#include <iostream>
 
int main()
{
    int a[4][4] ;
 
    std::cout << "enter array\n" ;
    for( int row = 0 ; row<4 ; ++row )
        for( int col = 0 ; col < 4 ; ++col )
            std::cin >> a[row][col] ;
 
    int b[16] ;
    int pos = 0 ;
    for( int row = 0 ; row<4 ; ++row )
        for( int col = 0 ; col < 4 ; ++col )
            b[pos++] = a[col][row] ;
 
    for( int k = 0 ; k < 16 ; ++k ) std::cout << b[k] << ' ' ;
    std::cout << '\n' ;
}
 

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