T1 数字三角形 输入a，输出由a行组成的数字三角形

样例输入：3

样例输出：

1

2 3

4 5 6

代码：

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#define LL long long
#define orz cout<<"creeper AK IOI!"<<endl

using namespace std;
const int MAXN = 1;
const int INF = 1;
const int mod = 1;

int n;

int read(){
	int s = 0, f = 0;
	char ch = getchar();
	while(!isdigit(ch))  f |= (ch == '-'), ch = getchar();
	while(isdigit(ch)) s = (s << 1) + (s << 3) + ch - '0' , ch = getchar();
	return f ? -s : s;
}

int main()
{
	n = read();
	int cnt = 0, sum = 1, T = 1;
	while(cnt < n){
		printf("%d ", ++cnt);
		if(sum == cnt){
			sum += ++T;
			printf("\n");
		}
	}
	return 0;
}