数学方法直接输出

#include<bits/stdc++.h>
using namespace std;
int main(void){
    int n; cin >> n;
    int c = 0,no = 0;
    for(int i = 1;i <= n;i++){
        for(int j = 1;j <= n;j++){
            c++;
            if(i % 2 == 0) cout << no * 2 - (j - 1) << " ";
            else{
                cout << c << " ";
                no++;
            }
        }
        cout << endl;
    }
    return 0;
}