From f036029205e23b15fe6175a02e2d8598c5a49f87 Mon Sep 17 00:00:00 2001
From: Samuel Oberhofer <sa.oberhofer@mci4me.at>
Date: Sat, 18 Jun 2022 17:21:38 +0200
Subject: [PATCH] 4.3

---
 Uebung 4/Uebung4_3/Makefile     | 52 +++++++++++++++++++++++++++++++++
 Uebung 4/Uebung4_3/digitSum.cpp | 18 ++++++++++++
 2 files changed, 70 insertions(+)
 create mode 100644 Uebung 4/Uebung4_3/Makefile
 create mode 100644 Uebung 4/Uebung4_3/digitSum.cpp

diff --git a/Uebung 4/Uebung4_3/Makefile b/Uebung 4/Uebung4_3/Makefile
new file mode 100644
index 0000000..d266e29
--- /dev/null
+++ b/Uebung 4/Uebung4_3/Makefile	
@@ -0,0 +1,52 @@
+
+# Name of the binary for Development
+BINARY = main
+# Name of the binary for Release
+FINAL = prototyp
+# Object files
+OBJS   = digitSum.o
+# Compiler flags
+CFLAGS = -Werror -Wall -std=c++17 -fsanitize=address,undefined -g
+# Linker flags
+LFLAGS = -fsanitize=address,undefined
+#Which Compiler to use
+COMPILER = c++
+
+
+# all target: builds all important targets
+all: binary
+
+final : ${OBJS}
+	${COMPILER} ${LFLAGS} -o ${FINAL} ${OBJS}
+	rm ${OBJS}
+
+binary : ${OBJS}
+	${COMPILER} ${LFLAGS} -o ${BINARY} ${OBJS}
+
+# Links the binary
+${BINARY} : ${OBJS}
+	${COMPILER} ${LFLAGS} -o ${BINARY} ${OBJS}
+
+
+# Compiles a source-file (any file with file extension .c) into an object-file
+#
+# "%" is a wildcard which matches every file-name (similar to * in regular expressions)
+# Such a rule is called a pattern rule (because it matches a pattern, see https://www.gnu.org/software/make/manual/html_node/Pattern-Rules.html),
+# which are a form of so called implicit rules (see https://www.gnu.org/software/make/manual/html_node/Implicit-Rules.html)
+# "$@" and "$<" are so called automatic variables (see https://www.gnu.org/software/make/manual/html_node/Automatic-Variables.html)
+%.o : %.cpp
+	${COMPILER} -c ${CFLAGS} -o $@ $<
+
+
+# Rules can not only be used for compiling a program but also for executing a program
+run: ${BINARY}
+	./${BINARY}
+
+
+# Delete all build artifacts
+clean :
+	rm -rf ${BINARY} ${OBJS}
+
+
+# all  and clean are a "phony" targets, meaning they are no files
+.PHONY : all clean
diff --git a/Uebung 4/Uebung4_3/digitSum.cpp b/Uebung 4/Uebung4_3/digitSum.cpp
new file mode 100644
index 0000000..873c390
--- /dev/null
+++ b/Uebung 4/Uebung4_3/digitSum.cpp	
@@ -0,0 +1,18 @@
+#include <iostream>
+#include <string>
+
+/*  algorithm that "hashes" the through digit sum. The size needed for
+ * this would be 64, since telephone numbers are exactly 7 digits long and the
+ * maximum value a digit can have is 9 -> 7*9 = 63, plus 1 since we start at
+ * zero. */
+int digitSum(std::string telNr) {
+  uint32_t number = std::stoi(telNr);
+  uint8_t digitSum = 0;
+  while (number > 0) {
+    digitSum += number % 10;
+    number /= 10;
+  }
+  return digitSum;
+}
+
+int main() { std::cout << digitSum("9797979") << std::endl; }
\ No newline at end of file