diff --git a/src/question_5.cpp b/src/question_5.cpp
index 1304f4a433387bd132de26536f9e16a40bf1a0e8..7ea1e205d56f593115909aa050baf83096d31e66 100644
--- a/src/question_5.cpp
+++ b/src/question_5.cpp
@@ -9,7 +9,7 @@
 #include <gmpxx.h>
 #include <cassert>
 
-time_t algo_sqrt(mpz_class const& a, mpz_class & res) 
+float algo_sqrt(mpz_class const& a, mpz_class & res) 
 {
 
   struct timespec t0, t1;
@@ -32,7 +32,7 @@ time_t algo_sqrt(mpz_class const& a, mpz_class & res)
 
   clock_gettime( CLOCK_REALTIME, &t1);
   
-  time_t t_res = 1000.*(t1.tv_sec-t0.tv_sec) + (t1.tv_nsec-t0.tv_nsec)/1000000.;
+  float t_res = 1000.*(t1.tv_sec-t0.tv_sec) + (t1.tv_nsec-t0.tv_nsec)/1000000.;
   return t_res;
 };
 
@@ -45,7 +45,7 @@ int main(int argc, char** argv) {
 
   mpz_class a = state.get_z_bits(n * 8 * sizeof(mp_limb_t));
   mpz_class res;
-  time_t t;
+  float t;
 
   t = algo_sqrt(a, res);