Gauss Elimination method in C language using Lower triangular matrix

This is a simple C language program that calculates solution of n-linear equations using Non-pivotal Gauss Elimination method. It uses lower triangular matrix to do so, for upper triangular matrix visit here.

#include<stdio.h>
#include<conio.h>
 
float matrix[10][10], m, temp[10];
int i, j, k, n;
 
void lower_traingularisation() {
    for (i=n-1; i>0; i--)
        for (j=i-1; j>=0; j--) {
            m	= matrix[j][i]/matrix[i][i];
            for (k=0; k<n+1; k++) {
                matrix[j][k]	= matrix[j][k]-(m*matrix[i][k]);
            }
        }
} //lower_traingularisation
 
void back_subsitution() {
    for (i=0; i<n; i++) {
        m	= matrix[i][n];
        for (j=0; j<i; j++)
            m	= m - temp[j] * matrix[i][j];
        temp[i]	= m/matrix[i][i];
        printf("\n x%d => %f", i+1, temp[i]);
    }
} // back_subsitution
 
void main() {
    printf("Enter number. of variables :: ");
    scanf("%d", &n);
 
    printf("Enter the augmented matrix: \n");
    for (i=0; i<n; i++)
        for (j=0; j<n+1; j++)
            scanf("%f", &matrix[i][j]);
 
    lower_traingularisation();
 
    printf("The lower traingular matrix is : \n");
 
    for (i=0; i<n; i++) {
        for (j=0; j<n+1; j++)
            printf("%f \t", matrix[i][j]);
        printf("\n");
    }
 
    printf("The required result is : \n");
 
    back_subsitution();
 
    getch();
} // main

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