1.6.cpp

#include <iostream>
using namespace std;

void swap(int &a, int &b){
    int t = a;
    a = b;
    b = t;
}
void transpose(int a[][4], int n){
    for(int i=0; i<n; ++i)
        for(int j=i+1; j<n; ++j)
            swap(a[i][j], a[j][i]);
    for(int i=0; i<n/2; ++i)
        for(int j=0; j<n; ++j)
            swap(a[i][j], a[n-1-i][j]);
}
int main(){
    int a[4][4] = {
        {1, 2, 3, 4},
        {5, 6, 7, 8},
        {9, 10, 11, 12},
        {13, 14, 15, 16}
    };
    for(int i=0; i<4; ++i){
        for(int j=0; j<4; ++j)
            cout<<a[i][j]<<" ";
        cout<<endl;
    }
    cout<<endl;
    transpose(a, 4);
    for(int i=0; i<4; ++i){
        for(int j=0; j<4; ++j)
            cout<<a[i][j]<<" ";
        cout<<endl;
    }
    return 0;
}