Refactor for clean root module and documentation

examples/simple_sat_program.rs

@@ -1,19 +1,24 @@
+use cp_sat::builder::CpModelBuilder;
+use cp_sat::proto::CpSolverStatus;
+
 fn main() {
-    let mut model = cp_sat::builder::CpModelBuilder::default();
+    let mut model = CpModelBuilder::default();
+
     let x = model.new_int_var_with_name([(0, 2)], "x");
     let y = model.new_int_var_with_name([(0, 2)], "y");
     let z = model.new_int_var_with_name([(0, 2)], "z");
-    model.add_all_different([x, y, z]);
-    println!("{:#?}", model);
-    println!("model stats: {}", model.stats());
+
+    model.add_ne(x, y);
+
     let response = model.solve();
-    println!("{:#?}", response);
     println!(
-        "response stats: {}",
-        cp_sat::cp_solver_response_stats(&response, false)
+        "{}",
+        cp_sat::ffi::cp_solver_response_stats(&response, false)
     );
-    assert_eq!(response.status(), cp_sat::proto::CpSolverStatus::Optimal);
-    assert!(x.solution_value(&response) != y.solution_value(&response));
-    assert!(x.solution_value(&response) != z.solution_value(&response));
-    assert!(y.solution_value(&response) != z.solution_value(&response));
+
+    if response.status() == CpSolverStatus::Optimal {
+        println!("x = {}", x.solution_value(&response));
+        println!("y = {}", y.solution_value(&response));
+        println!("z = {}", z.solution_value(&response));
+    }
 }