diff --git a/src/main/c/BasicMode.c b/src/main/c/BasicMode.c
index da2431d..7cab631 100644
--- a/src/main/c/BasicMode.c
+++ b/src/main/c/BasicMode.c
@@ -52,6 +52,17 @@ long long int multiplication(long long int a, long long int b) {
 
     return dec2;
 }
+//subtraction
+long long int subtraction(long long int a, long long int b) {
+    long long int dec1, dec2;
+    dec1 = BinToDec(a);
+    dec2 = BinToDec(b);
+    dec1 = dec1 - dec2;
+    dec2 = DecToBin(dec1);
+
+    return dec2;
+}
+
 
 int main() {