3 files changed, 101 insertions, 2 deletions
diff --git a/8p11.cpp b/8p11.cpp
index 267e692..49a7825 100644
--- a/8p11.cpp
+++ b/8p11.cpp
@@ -32,9 +32,9 @@ int main () {
 		people.push_back(info);
 	}
 
-	for(auto &a : people) {
+	for(const auto &a : people) {
 		std::cout << a.name << "\n";
-		for(auto &b : a.phones) {
+		for(const auto &b : a.phones) {
 			std::cout << b << "\n";
 		}
 	}
diff --git a/8p13.cpp b/8p13.cpp
new file mode 100644
index 0000000..89de819
--- /dev/null
+++ b/8p13.cpp
@@ -0,0 +1,78 @@
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+#include <fstream>
+#include <filesystem>
+#include <libgen.h>
+
+/*
+ *
+ * 8.13
+ *
+ *
+ */
+
+struct PersonInfo {
+	std::string name;
+	std::vector<std::string> phones;
+};
+
+int valid(const std::string &nums) {
+
+	if(nums[0] == '1') {
+		return 0;
+	}
+	
+	return 1;
+}
+
+std::string format(std::string phones) {
+
+	return phones;
+}
+
+int main (int argc, char **argv) {
+
+	if(argc < 2 || argc > 2) {
+		return -1;
+	}
+
+	std::ifstream file(argv[1]);
+	if(file.fail()) {
+		std::cerr << argv[0] << ": no such file '" << basename(argv[1]) << "'" << std::endl;
+		return -1;
+	}
+
+	std::string line;
+	std::string word;
+	std::vector<PersonInfo> people;
+	while (getline(file, line)) {
+		PersonInfo info;
+		std::istringstream record(line);
+		record >> info.name; 
+		while (record >> word)
+			info.phones.push_back(word);
+		people.push_back(info); 
+	}
+	
+	for (const auto &entry : people) {
+		std::ostringstream formatted;
+		std::ostringstream badNums;
+		for (const auto &nums : entry.phones) {
+			if (!valid(nums)) {
+				badNums << " " << nums;
+			} else
+				formatted << " " << format(nums);
+		}
+		if (badNums.str().empty()) {
+			std::cout << entry.name << " "
+			   << formatted.str() << std::endl;
+		} else {
+			std::cerr << "input error: " << entry.name
+					  << " invalid number(s) " << badNums.str() << std::endl;
+		}
+	}
+	
+	return 0;
+}
diff --git a/8p14.cpp b/8p14.cpp
new file mode 100644
index 0000000..1fc3c1e
--- /dev/null
+++ b/8p14.cpp
@@ -0,0 +1,21 @@
+
+/*
+ *
+ * 8.14
+ *
+ *
+ */
+
+int main () {
+
+	/*
+
+	  They are references because the vectors could be very
+	   large and passing a reference means it does not have to
+	   be copied.
+
+	   Const is because the data only needs to be read.
+
+	*/
+	return 0;
+}