Blue Bridge Cup questions basic training Triangle

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Topic links : http://lx.lanqiao.cn/problem.page?gpid=T10

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Subject description:

Resource constraints

Time limit: 1.0s Memory Limit: 256.0MB

Problem Description

Triangle known as Pascal triangle, its first row i + 1 is (a + b) i-expanding coefficient.　

It is an important property: triangles each number equal to its two shoulders numbers together.

We are given below of the first four rows Triangle:
　　

   1

　　

  1 1

　　

 1 2 1

　　

1 3 3 1

　　

Given n, the first n rows outputs it.

Input Format

Input contains a number n.

Output Format

The output of the first n rows Triangle. Each row from the first row are sequentially output number, using one intermediate spaces. Please do not print extra spaces in front.

Sample input

4

Sample Output

1
1 1
1 2 1
1 3 3 1

Data size and convention

1 <= n <= 34。

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 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 const int MAXN=100;
 4 int a[MAXN][MAXN];
 5 int main(){
 6     int n;
 7     cin>>n;
 8     for(int i=0;i<n;i++){
 9         a[i][0]=a[i][i]=1;
10         for(int j=1;j<i;j++){
11             a[i][j]=a[i-1][j]+a[i-1][j-1];
12         }
13     }
14     for(int i=0;i<n;i++){
15         for(int j=0;j<=i;j++){
16             cout<<a[i][j]<<"   ";
17         }
18         cout<<endl;
19     }
20     return 0;
21 }