diff --git a/src/BTCSDiffusion.cpp b/src/BTCSDiffusion.cpp
index 919a1e5..9a92418 100644
--- a/src/BTCSDiffusion.cpp
+++ b/src/BTCSDiffusion.cpp
@@ -19,17 +19,28 @@
 const BCSide BTCSDiffusion::LEFT = 0;
 const BCSide BTCSDiffusion::RIGHT = 1;
 
-BTCSDiffusion::BTCSDiffusion(int x) : dim_x(x) { this->grid_dim = 1; }
+BTCSDiffusion::BTCSDiffusion(int x) : dim_x(x) {
+  this->grid_dim = 1;
+  this->bc.reserve(2);
+}
 BTCSDiffusion::BTCSDiffusion(int x, int y) : dim_x(x), dim_y(y) {
 
   this->grid_dim = 2;
+  this->bc.reserve(x * 2 + y * 2);
 }
 BTCSDiffusion::BTCSDiffusion(int x, int y, int z)
     : dim_x(x), dim_y(y), dim_z(z) {
 
   this->grid_dim = 3;
+  //TODO: reserve memory for boundary conditions
 }
 
+void BTCSDiffusion::setBoundaryCondition(std::vector<double> input,
+                                         BCSide side) {
+  if (this->grid_dim == 1) {
+    bc[side] = input[0];
+  }
+}
 void BTCSDiffusion::simulate(std::vector<double> &c, std::vector<double> &alpha,
                              double timestep) {
   double dx = 1. / this->dim_x;
diff --git a/src/test_class.cpp b/src/test_class.cpp
new file mode 100644
index 0000000..48d8b14
--- /dev/null
+++ b/src/test_class.cpp
@@ -0,0 +1,33 @@
+#include "BTCSDiffusion.hpp"
+#include "diffusion.hpp"
+#include <cmath>
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+int main(int argc, char *argv[]) {
+
+  int x = 20;
+
+  std::vector<double> alpha(x, 1 * pow(10, -1));
+  std::vector<double> input(x, 1 * std::pow(10, -6));
+  std::vector<double> bc_left, bc_right;
+
+  bc_left.push_back(5. * std::pow(10, -6));
+  bc_right.push_back(1. * std::pow(10, -6));
+  // input[x + 2] = 5.5556554 * std::pow(10, -6);
+  // input[x + 3] = 5.234564213 * std::pow(10, -6);
+
+  BTCSDiffusion diffu(x);
+
+  diffu.setBoundaryCondition(bc_left, BTCSDiffusion::LEFT);
+  diffu.setBoundaryCondition(bc_right, BTCSDiffusion::RIGHT);
+
+  for (int i = 0; i < 100; i++) {
+    diffu.simulate(input, alpha, 1.);
+    // BTCS1D(x, input, alpha, 1., bc);
+  }
+
+  return 0;
+}