GESP Level 2 exercise, multi-layer loop practice, difficulty ★✮☆☆☆.
luogu-T259140 Triangle
Problem Requirements
Problem Description
Given , please output a right-angled triangle with the length of the right angle being . All numbers are composed of digits, and if there are not enough digits, leading should be added.
Tip: Use
<span>printf("%02d",x);</span>to automatically add leading zeros for single-digit numbers.
Input Format
Input a positive integer .
Output Format
Output the numeric right-angled triangle as required by the problem.
Sample Input #1
5
Sample Output #1
0102030405
06070809
101112
1314
15
Data Range
The data guarantees that .
Problem Analysis
This is a simple mathematical problem, and we can use two nested loops to print the numeric right-angled triangle. The outer loop controls the number of rows, while the inner loop controls the number of digits in each row. We use a variable b to represent the current number, and after printing a number, b is incremented by 1. When b is a single-digit number, we use the printf function to print it, keeping two decimal places. When b is a two-digit number, we print it directly.
Example Code
#include <cstdio>
#include <iostream>
using namespace std;
int main() {
int a; // Define variable a
cin >> a; // Input a
int b = 1; // Define variable b and initialize to 1
for (int i = a; i > 0; i--) { // Outer loop, controls the number of rows
for (int j = 1; j <= i; j++) { // Inner loop, controls the number of digits in each row
if (b / 10 == 0) { // If b is a single-digit number
printf("%.02d", b); // Output b, keeping two decimal places
} else { // If b is a two-digit number
printf("%d", b); // Output b directly
}
b++; // Increment b
}
cout << endl; // New line
}
return 0; // Return 0, indicating normal program termination
}
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[Top][GESP] C++ Certification Learning Resource Summary
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