正确答案是这样
using System;
using System.Collections.Generic;
using System.Text;
namespace Test
{
class Program
{
static void Main(string[] args)
{
for (int y = 1; y <= 7; y++)
{
for (int x = 1; x <= y; x++)
{
Console.Write(x);
}
Console.WriteLine();//换行
}
}
}
}