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Home coding Write a program to print pascal triangle.

# Write a program to print pascal triangle.

Given a number we have to print pascal triangle.

So what is Pascal triangle ?

Pascal Triangle is a triangle of triangular array of binomial coefficent.

Example:

``````input:5

output:
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
``````

Logic:

``we will make 2d array as we see current value is sum of previous two values ,so we store previous value to  array.``

Code-

```#include <bits/stdc++.h>
using namespace std;
int main()
{
int num;
cout<<"enter rows of pascal "<<endl;
cin>>num;

///lets print the pascal triangle.

int pas[num][num];
for (int j=0; j<num; j++) //iterating lines
{

for (int i = 0; i <= j; i++)
{

if (j == i || i == 0)
{
pas[j][i] = 1;
}
else
{
pas[j][i] = pas[j-1][i - 1] + pas[j- 1][i];
}
cout << pas[j][i] << " ";
}
cout<<endl;
}

}

```

Output:

```enter no of row :5
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1```

Time complexity:0(N*N)

Space Complexity:O(N*N)

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