diff --git a/ai/aron/aiboard.cc b/ai/aron/aiboard.cc
index a92b91fee9b50765071357193a89be481087642d..f0c685a4200039654bd6413d756c588333d9c86e 100644
--- a/ai/aron/aiboard.cc
+++ b/ai/aron/aiboard.cc
@@ -25,7 +25,7 @@
 
 #include "aiboard.h"
 
-#include <time.h>
+#include <ctime>
 
 #include <vector>
 #include <iostream>
@@ -81,7 +81,7 @@ usi AiBoard::height() const {
 
 Coord AiBoard::move() {
     if (m_cleanBoard) {
-        qsrand(static_cast<int>(time(0)));
+        qsrand(static_cast<int>(std::time(nullptr)));
         usi randX = qrand()%(m_dimension->width()/3) + m_dimension->width()/3;
         usi randY = qrand()%(m_dimension->height()/3) + m_dimension->height()/3;
         return Coord(randX, randY);
diff --git a/ai/gabor/ai_impl.cpp b/ai/gabor/ai_impl.cpp
index 0aa69c82218cc4947fdd9f57c8a9948c5d60a811..832fe3357a3b2a73ce32467e075048794a5ec95c 100644
--- a/ai/gabor/ai_impl.cpp
+++ b/ai/gabor/ai_impl.cpp
@@ -27,7 +27,7 @@
 #include <cstdlib>
 #include <memory.h>
 #include <assert.h>
-#include <time.h>
+#include <ctime>
 #include <stdio.h>
 
 // hash table
@@ -45,7 +45,7 @@ AiImpl::AiImpl() : table_size_x(20), table_size_y(20),
 {
 	if (!rand_inited) {
 		rand_inited = true;
-		qsrand((unsigned int) time(NULL));
+		qsrand(static_cast<unsigned int>(std::time(nullptr)));
 	}
 	memset(hashData, 0, sizeof(hashData));
 }
diff --git a/ai/gabor/node.cpp b/ai/gabor/node.cpp
index 2b16e720d0731c3f8079ed51c70e635522a9e4e2..406c2e782b618e8ad3ad2fbe8779b38e20b3b76e 100644
--- a/ai/gabor/node.cpp
+++ b/ai/gabor/node.cpp
@@ -25,7 +25,6 @@
 #include "standing.h"
 
 #include <assert.h>
-#include <time.h>
 
 Node::Node(Standing* _standing, AiImpl* ai):
 	standing(_standing),