diff --git a/calculator.cpp b/calculator.cpp
index df0040b..83b8972 100644
--- a/calculator.cpp
+++ b/calculator.cpp
@@ -14,3 +14,12 @@ int Calculator::Mul (double a, double b)
 {
     return a * b + 0.5;
 }
+
+double Calculator::Pow(double a, int n)
+{
+	double result = 1;
+	for (int i = 0; i < n; i++) {
+		result *= a;
+	}
+	return result;
+}
diff --git a/calculator.h b/calculator.h
index bd40bcd..d8b121a 100644
--- a/calculator.h
+++ b/calculator.h
@@ -7,7 +7,7 @@ class Calculator
 		int Add (double, double);
 		int Sub (double, double);
 		int Mul (double, double);
->>>>>>> e0ea21b (add a multiplication operation)
+		double Pow (double, int);
 };
 
 #endif//CALCULATOR_H
diff --git a/patches/0001-fix-truncation-error.patch b/patches/0001-fix-truncation-error.patch
new file mode 100644
index 0000000..6e2c95d
--- /dev/null
+++ b/patches/0001-fix-truncation-error.patch
@@ -0,0 +1,30 @@
+From 49150debe027e79690fd713db43e17e4f0b7341f Mon Sep 17 00:00:00 2001
+From: Sergii Piatakov <sergii.piatakov@globallogic.com>
+Date: Thu, 15 Nov 2018 15:28:04 +0200
+Subject: [PATCH] fix truncation error
+
+To convert float to integer the truncation is performed, but the
+rounding is expected.
+
+Test: Add (4.9, 4.9) should return 10.
+Signed-off-by: Sergii Piatakov <sergii.piatakov@globallogic.com>
+---
+ calculator.cpp | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/calculator.cpp b/calculator.cpp
+index f323e14..d10f529 100644
+--- a/calculator.cpp
++++ b/calculator.cpp
+@@ -2,7 +2,7 @@
+ 
+ int Calculator::Add (double a, double b)
+ {
+-	return a + b;
++	return a + b + 0.5;
+ }
+ 
+ int Calculator::Sub (double a, double b)
+-- 
+2.43.0
+
diff --git a/patches/0001-formatting-use-tabs-instead-of-spaces.patch b/patches/0001-formatting-use-tabs-instead-of-spaces.patch
new file mode 100644
index 0000000..3ddcd5a
--- /dev/null
+++ b/patches/0001-formatting-use-tabs-instead-of-spaces.patch
@@ -0,0 +1,48 @@
+From b239ff832843c03fafeef255c21fc586645fa4bd Mon Sep 17 00:00:00 2001
+From: Sergii Piatakov <sergii.piatakov@globallogic.com>
+Date: Thu, 15 Nov 2018 15:26:35 +0200
+Subject: [PATCH] formatting: use tabs instead of spaces
+
+Signed-off-by: Sergii Piatakov <sergii.piatakov@globallogic.com>
+---
+ calculator.cpp | 4 ++--
+ calculator.h   | 6 +++---
+ 2 files changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/calculator.cpp b/calculator.cpp
+index b91afea..f323e14 100644
+--- a/calculator.cpp
++++ b/calculator.cpp
+@@ -2,10 +2,10 @@
+ 
+ int Calculator::Add (double a, double b)
+ {
+-    return a + b;
++	return a + b;
+ }
+ 
+ int Calculator::Sub (double a, double b)
+ {
+-    return Add (a, -b);
++	return Add (a, -b);
+ }
+diff --git a/calculator.h b/calculator.h
+index 3740907..d59d596 100644
+--- a/calculator.h
++++ b/calculator.h
+@@ -3,9 +3,9 @@
+ 
+ class Calculator
+ {
+-    public:
+-        int Add (double, double);
+-        int Sub (double, double);
++	public:
++		int Add (double, double);
++		int Sub (double, double);
+ };
+ 
+ #endif//CALCULATOR_H
+-- 
+2.43.0
+