⚡ TL;DR
Print the pascal's triangle pattern in Dart. Complete working code, expected output, algorithm explanation, and practice variations for beginners learning loops.
The Pascal’s Triangle pattern is a classic loop exercise. Here’s the complete implementation in Dart with working code and output.
Pattern to Print
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1Implementation
void main() {
int n = 5;
for (int i = 0; i < n; i++) {
int num = 1;
String row = ' ' * (n - i);
for (int j = 0; j <= i; j++) { row += num.toString() + ' '; num = num * (i - j) ~/ (j + 1); }
print(row);
}
}Output
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1How It Works
Each element is computed with the multiplicative formula: value = previous * (row - col) / (col + 1).
Practice Variations
- Try printing the pattern with a different character (e.g.,
#or+) - Modify the code to accept the pattern size as user input
- Combine this pattern with its inverse to create a more complex shape
Complexity
- Time: O(n²) — the grid or line count grows quadratically
- Space: O(1) — only loop counters are needed
Related Patterns
- Pascal’s Triangle in Python
- Pascal’s Triangle in Go
- Pascal’s Triangle in Swift
- Palindromic Number Pyramid in Dart
- Number Pyramid in Dart
- Number Triangle in Dart
FAQ
How do you print the Pascal’s Triangle pattern in Dart?
Use nested loops: the outer loop walks through the rows while the inner loop prints the characters or values for each row. The complete Dart implementation with expected output is shown in the sections above.
What is the time complexity of the Pascal’s Triangle pattern in Dart?
The time complexity is O(n²) and the space complexity is O(1), since the pattern is built with a fixed number of loop counters and printed row by row.
Happy coding!
