سلام.من در برنامه ویژوال استودیو 2015 به زبان c , c++ برنامه می نویسم اما گاهی اوقات ارور می دهد.

به طور به مثال دلیل ارور زیر چیست:

#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <iostream>
#include "stdafx.h"
using namespace std;
int main(void)
{
	srand(time(0));
	int x = rand();
	printf("%d is\n", x);
	return 0;
}

خطا:

Severity	Code	Description	Project	File	Line	Suppression State
Warning	C4627	'#include <stdlib.h>': skipped when looking for precompiled header use	addad tasadofi	f:\project\visual studio\addad tasadofi\addad tasadofi\addad tasadofi.cpp	1	
Warning	C4627	'#include <iostream>': skipped when looking for precompiled header use	addad tasadofi	f:\project\visual studio\addad tasadofi\addad tasadofi\addad tasadofi.cpp	4	
Warning	C4627	'#include <time.h>': skipped when looking for precompiled header use	addad tasadofi	f:\project\visual studio\addad tasadofi\addad tasadofi\addad tasadofi.cpp	3	
Error	C3861	'rand': identifier not found	addad tasadofi	f:\project\visual studio\addad tasadofi\addad tasadofi\addad tasadofi.cpp	10	
Error	C3861	'srand': identifier not found	addad tasadofi	f:\project\visual studio\addad tasadofi\addad tasadofi\addad tasadofi.cpp	9	
Error	C3861	'time': identifier not found	addad tasadofi	f:\project\visual studio\addad tasadofi\addad tasadofi\addad tasadofi.cpp	9