#include <stdio.h>

int main() {
  double a[3][3] = {{2, 1, -1}, {-3, -1, 2}, {-2, 1, 2}};
  double b[3] = {8, -11, -3};
  int n = 3;

  for (int k = 0; k < n - 1; k++) {
    for (int i = k + 1; i < n; i++) {
      double factor = a[i][k] / a[k][k];
      for (int j = k; j < n; j++) a[i][j] -= factor * a[k][j];
      b[i] -= factor * b[k];
    }
  }

  double x[3];
  for (int i = n - 1; i >= 0; i--) {
    x[i] = b[i];
    for (int j = i + 1; j < n; j++) x[i] -= a[i][j] * x[j];
    x[i] /= a[i][i];
  }

  printf("x = %.4f, y = %.4f, z = %.4f\n", x[0], x[1], x[2]);
  return 0;
}