Example 1: Triangle Pattern – I
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
// inner loop runs for n
for (let num = 1; num <= n; num++) {
pattern += num;
}
// Add a new line character after contents of each line
pattern += "n";
}
console.log(pattern);
Example 2: Triangle Pattern – II
1
2 2
3 3 3
4 4 4 4
5 5 5 5 5
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
// inner loop runs for n
for (let num = 1; num <= n; num++) {
pattern = pattern+n;
}
// Add a new line character after contents of each line
pattern += "n";
}
console.log(pattern);
Example 3 : Triangle Pattern – III
1
2 3
4 5 6
7 8 9 10
let rows = 4;
// variable contains the next element of the pattern
let variable = 1;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
for (let num = 1; num <= n; num++) {
pattern += variable+" ";
variable++;
}
pattern += "n";
}
console.log(pattern);
Example 4: Number Pyramid Pattern – I
1
123
12345
1234567
123456789
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
// Inner Loop - I -> for the spaces
for (let space = 1; space <= rows - n; space++) {
pattern += " ";
}
// Inner Loop - II -> for the numbers
for (let num = 1; num <= 2 * n - 1; num++) {
pattern += num;
}
pattern += "n";
}
console.log(pattern);
Example 5: Square Star Pattern – I
*****
*****
*****
*****
*****
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
// Inner loop for printing stars
for (let num = 1; num <= 5; num++) {
pattern += "*";
}
pattern += "n";
}
console.log(pattern);
Example 6: Square Star Pattern – II
*****
* *
* *
* *
*****
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
for (let num = 1; num <= 5; num++) {
// print star only if it is the boundary location
if (n == 1 || n == rows) pattern += "*";
else {
if (num == 1 || num == 5) {
pattern += "*";
} else {
pattern += " ";
}
}
}
pattern += "n";
}
console.log(pattern);
Example 7 : Right Triangle Pattern
*
**
***
****
*****
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
// Inner loop - I -> prints spaces
for (let space = 1; space <= rows - n; space++) {
pattern += " ";
}
// Inner Loop - II -> prints stars
for (let num = 1; num <= n; num++) {
pattern += "*";
}
pattern += "n";
}
console.log(pattern);
Example 8 : Pyramid Triangle Pattern
*
***
*****
*******
*********
let rows = 5;
// pattern variable carries the final pattern in string format
let pattern = "";
// outer loop runs for `rows` no. of times
for (let n = 1; n <= rows; n++) {
// Inner Loop - I -> prints spaces
for (let space = 1; space <= rows - n; space++) {
pattern += " ";
}
// Inner Loop - II -> prints stars
for (let num = 1; num <= 2 * n - 1; num++) {
pattern += "*";
}
pattern += "n";
}
console.log(pattern);
