Codeforces Round 896 (Div. 2)

A. Make It Zero

代码:

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using i128 = __int128;
int n, m;

void solve()
{
    scanf("%d", &n);
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++)
    {
        scanf("%d", &a[i]);
    }
    if (n & 1)
    {
        printf("4\n");
        printf("2 %d\n", n);
        printf("2 %d\n", n);
        printf("1 2\n");
        printf("1 2\n");
    }
    else
    {
        printf("2\n");
        printf("1 %d\n", n);
        printf("1 %d\n", n);
    }
}

int main()
{
    int t = 1;
    scanf("%d", &t);
    while (t--)
    {
        solve();
    }
    return 0;
}