Gauss Elimination problem solution in C language

Gauss Elimination problem solution in C language

	/**
	Gauss Elimination problem solution in C language [Basic]
	@author : Maniruzzaman Akash
	**/
	#include<stdio.h>
	int main(){
	int i, j, k, n;
	float matrix[100][100];
	float sum = 0.0;
	float x[100]; //Keep the values in it
	float temp = 0.0;
	printf("Please enter the order of the matrix : ");
	scanf("%d", &n);
	//Take the matrix value from the scan
	for(i = 1; i <= n; i++){
	for(j = 1; j <= n+1; j++){
	printf("Enter Matrix value for Mat[%d][%d] :", i, j);
	scanf("%f", &matrix[i][j]);
	}
	}
	printf("\n");
	//Show the matrix entered by the user
	for(i = 1; i <= n; i++){
	for(j = 1; j <= n; j++){
	printf("%f ", matrix[i][j]);
	}
	printf("\n");
	}
	//Make an upper triangular matrix first
	for(j = 1; j <= n; j++){
	for(i = 1; i <= n; i++){
	if(i > j){
	temp = matrix[i][j] / matrix[j][j];
	for(k = 1; k <= n + 1; k++){
	matrix[i][k] = matrix[i][k] - temp * matrix[j][k];
	}
	}
	}
	}
	x[n]= matrix[n][n+1] / matrix[n][n];
	//Backward substitution
	for(i=n-1; i>=1; i--){
	sum = 0;
	for(j = i+1; j <= n; j++)
	{
	sum = sum+matrix[i][j]*x[j];
	}
	x[i]=(matrix[i][n+1]-sum) / matrix[i][i];
	}
	printf("The values are : \n");
	for(i=1; i<=n; i++)
	{
	printf("\nx%d=%f\t",i,x[i]);
	}
	return 0;
	}

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This is the simple problem of Gauss Elimination. Some few steps you have to follow here:

Step: 1) 
Take the value in an array by creating two loops for the matrix

Step: 2) 
Make forward substitution for getting the top right values from the matrix.

Step: 3) 
Make backword substitution for replcaing one value to another and get the exact values, like X1, X2 etc.