题解

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    cin>>n;
    int a[n][n];
    for (int i=0;i<n;i++){
    	a[i][0]=1,a[i][i]=1;
	}
    for (int i=2;i<n;i++){
        for (int j=1;j<i;j++){
        	a[i][j]=a[i-1][j]+a[i-1][j-1];
		}
    }
    for (int i=0;i<n;i++){
        for (int j=0;j<=i;j++)
            cout<<a[i][j]<<" ";
        	cout<<endl;
    }
    return 0;
}