diff --git a/src/addition.c b/src/addition.c
index d43de60..208161a 100644
--- a/src/addition.c
+++ b/src/addition.c
@@ -17,7 +17,7 @@ struct data
 struct datad {
     union {
         double dnum;
-        unsigned long lnum;
+        unsigned long long lnum;
     } number;
     unsigned long sign;
     unsigned long exponent;
@@ -111,12 +111,12 @@ float addition_float(float number1, float number2) {
     return num3.number.floating;
 }
 
-unsigned long sign_double(unsigned long a) {
+unsigned long long sign_double(unsigned long long a) {
     if (a & 0x8000000000000000 == 0x8000000000000000) return 1;
     else return 0;
 }
 
-unsigned long precision_double(unsigned long a) {
+unsigned long long precision_double(unsigned long long a) {
     a &= 0x000fffffffffffff;
     return a;
 }
\ No newline at end of file
diff --git a/src/addition.h b/src/addition.h
index c770bd8..e02a55a 100644
--- a/src/addition.h
+++ b/src/addition.h
@@ -23,8 +23,8 @@ unsigned int output_float(unsigned int sign, unsigned int exponent, unsigned int
 
 float addition_float(float number1, float number2);
 
-unsigned long sign_double(unsigned long a);
+unsigned long long sign_double(unsigned long long a);
 
-unsigned long precision_double(unsigned long a);
+unsigned long long precision_double(unsigned long long a);
 
 #endif // ADDITION_H
\ No newline at end of file
diff --git a/test/test_addition.c b/test/test_addition.c
index ae4f1e7..ad81d17 100644
--- a/test/test_addition.c
+++ b/test/test_addition.c
@@ -15,7 +15,7 @@ union {
 
 union {
     double dnum;
-    unsigned long lnum;
+    unsigned long long lnum;
 } numberd[6];
 
 void setUp(void)
@@ -286,8 +286,8 @@ void test_addition_addition_float_sumofpositivnumbers(void)
 
 void test_addition_sign_double_numbers(void)
 {
-    unsigned long result[2];
-    unsigned long expected[2] = { 1, 0 };
+    unsigned long long result[2];
+    unsigned long long expected[2] = { 1, 0 };
     numberd[0].dnum = -3004683105640520235, numberd[1].dnum = 0.05313546453135;
     
     result[0] = sign_double(numberd[0].lnum);