added cross-platform

Planner/String.h

@@ -3,7 +3,7 @@
 #include <stdio.h>     
 #include <stdlib.h>     
 #include <string.h>    
-#include <ctype.h> 
+#include <ctype.h>
 
 class String {
 	friend String operator+(const String& a, const String& b);
@@ -17,14 +17,14 @@ public:
 	}
 
 	String(const char* s) {
-		length = strlen(s);
+		length = (long)strlen(s);
 		body = new char[length + 1];
 		for (long i = 0; i < length; ++i)
 			body[i] = s[i];
 		body[length] = '\0';
 	}
 	String(const char* s, char ps) {
-		length = strlen(s);
+		length = (long)strlen(s);
 		body = new char[length + 1];
 		for (long i = 0; i < length; ++i) {
 			body[i] = (s[i] == ps) ? '\n' : s[i];