Add problem 6 solutions

include/p6.h

@@ -0,0 +1,7 @@
+#ifndef P6_H
+#define P6_H
+
+void str_to_upper(char* str);
+
+#endif
+

src/main.c

@@ -5,6 +5,7 @@
 #include "p3.h"
 #include "p4.h"
 #include "p5.h"
+#include "p6.h"
 
 void print_int_arr(int* arr, int size) {
 	for (int i = 0; i < size; ++i) {
@@ -53,9 +54,19 @@ int main(void) {
 
 	// Problem 5
 	printf("Problem 5:\n");
+
 	int num_alphanum = count_alphanumeric("Hello World!!");
 	printf("Number of alphanumeric characters in \"Hello World!!\": %d\n", num_alphanum);
 
+	// Problem 6
+	printf("Problem 6:\n");
+
+	char p6_str[32] = "I have 3$, wow!";
+
+	printf("\"%s\"\n", p6_str);
+	str_to_upper(p6_str);
+	printf("\"%s\"\n", p6_str);
+
 	return 0;
 }
 

src/p6.c

@@ -0,0 +1,17 @@
+#include "p6.h"
+
+#define _CRT_SECURE_NO_WARNINGS
+
+#include <ctype.h>
+
+void str_to_upper(char* str) {
+	char* current = str;
+
+	while (*current != '\0') {
+		*current = toupper(*current);
+
+		++current;
+	}
+}
+
+