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Reverse Matrix

Lesson 20 of 25 in Coddy's Coding Problems: Volume 2 course.

 

Given a matrix, your task is to find every element that is below and including the main diagonal and reverse them from positive to negative, or negative to positive. First, you will receive a number N representing the rows and columns of the matrix and after that, you will receive each row on its own


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challenge icon

Challenge

Easy

Write a program that reads a natural number N from input and then inputs a NxN matrix of N rows and N columns. Change the sign in front of the numbers that are below and including the main diagonal and output the matrix again

Input
5
1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25

Output
-1 2 3 4 5
-6 -7 8 9 10
-11 -12 -13 14 15
-16 -17 -18 -19 20
-21 -22 -23 -24 -25

Note: For the result to be correct you need to print out one whitespace specifically after each row

Try it yourself

#include <stdio.h>

int main() {
    // Write code here
    return 0;
}

All lessons in Coding Problems: Volume 2