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Nested Loops
Nested Loops
- What Is a Nested Loop? A nested loop is a loop within a loop.
- Syntax Here, a for loop nested inside a for loop. However, any loop can be nested inside any loop. The general syntax is:
Example
The following code prints a multiplication table of 1-5 using a nested for loop.
fn main() {
for i in 1..5{ //outer loop
println!("Multiplication Table of : {}", i);
for j in 1..5 { // inner loop
println!("{} * {} = {}", i, j, i * j);
}
}
}
output
Multiplication Table of : 1
1 * 1 = 1
1 * 2 = 2
1 * 3 = 3
1 * 4 = 4
Multiplication Table of : 2
2 * 1 = 2
2 * 2 = 4
2 * 3 = 6
2 * 4 = 8
Multiplication Table of : 3
3 * 1 = 3
3 * 2 = 6
3 * 3 = 9
3 * 4 = 12
Multiplication Table of : 4
4 * 1 = 4
4 * 2 = 8
4 * 3 = 12
4 * 4 = 16
Explanation
Outer for Loop
- A for loop is defined on line 2
- The loop takes i as an iterator that iterates over values from 1 to 5.
Inner for Loop
- A for loop is defined on line 4
- The loop takes j as an iterator that iterates over values from 1 to 5.
- For each iteration of the outer loop, the inner loop runs four times while printing the product of variables i and j.
i | j | output |
---|---|---|
1 | 1 2 3 4 | 1 * 1 = 1 1 * 2 = 2 1 * 3 = 3 1 * 4 = 4 |
2 | 1 2 3 4 | 2 * 1 = 2 2 * 2 = 4 2 * 3 = 6 2 * 4 = 8 |
3 | 1 2 3 4 | 3 * 1 = 3 3 * 2 = 6 3 * 3 = 9 3 * 4 = 12 |
4 | 1 2 3 4 | 4 * 1 = 4 4 * 2 = 8 4 * 3 = 12 4 * 4 = 16 |
Sometimes, you might need to break the outer loop instead of the inner loop. So how can you specify which loop you are referring to? You can use a loop label.
Last updated 25 Jan 2024, 05:11 +0530 .