compile failed fix

.gitignore

@@ -0,0 +1,32 @@
+# Prerequisites
+*.d
+
+# Compiled Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Compiled Dynamic libraries
+*.so
+*.dylib
+*.dll
+
+# Fortran module files
+*.mod
+*.smod
+
+# Compiled Static libraries
+*.lai
+*.la
+*.a
+*.lib
+
+# Executables
+*.exe
+*.out
+*.app

main.cpp

@@ -3,10 +3,13 @@
 #include <cstdlib>
 #include <signal.h>
 #include <ctime>
+#include <sys/time.h>
 using namespace std;
 
 int random_num(int lo,int hi) { // contributed by a_k_n, https://www.cplusplus.com/forum/general/107917/
-	srand(time(NULL));
+	struct timeval time_now{};
+	gettimeofday(&time_now, nullptr);
+	srand(time_now.tv_usec);
 	return rand()%(hi-lo) + lo;
 }
 
@@ -23,11 +26,22 @@ int main() {
 	cout << "Guess a 2 digit number!" << endl;
 	signal(SIGINT, sigint_handler);
 	while(1) {
-		cout << guess_attempt++ << " guess attempt: ";
+		cout << guess_attempt+1 << " guess attempt: ";
 		int x;
 		cin >> x;
 		++guess_attempt;
-		if ( x == rand_guess_int ) {
+		if (cin.fail()) {
+			cout << "INVALID NUMBER, NOT AN INT!" << endl;
+			std::cin.clear();
+        		std::cin.ignore(256,'\n');
+        		--guess_attempt;
+		} else if ( x < 10 ) {
+			cout << "INVALID NUMBER! numbers should bigger then 9" << endl;
+			--guess_attempt;
+		} else if ( x > 99 ) {
+			cout << "INVALID NUMBER! numbers should smaller then 100" << endl;
+			--guess_attempt;
+		} else if ( x == rand_guess_int ) {
 			cout << "YAY! The secret number is " << rand_guess_int << ", you success within " << guess_attempt << " attempts!" << endl;
 			return 0;
 		} else if ( x < rand_guess_int ) {