1 files changed, 22 insertions, 0 deletions
diff --git a/ch2/2-10.c b/ch2/2-10.c
index e69de29..619e2d1 100644
--- a/ch2/2-10.c
+++ b/ch2/2-10.c
@@ -0,0 +1,22 @@
+#include <stdio.h>
+
+#define MAX_LEN 20
+
+void lower(char* source, char* dest);
+
+int main() {
+    char* s = "This Is A Test.";
+    char lower_s[MAX_LEN];
+    lower(s, lower_s);
+    printf("%s -> %s\n", s, lower_s);
+    return 0;
+}
+
+void lower(char* source, char* dest) {
+    int i;
+
+    for (i = 0; source[i] != '\0'; i++)
+        dest[i] = source[i] >= 'A' && source[i] <= 'Z' ? source[i] - 'A' + 'a' : source[i];
+
+    dest[i] = '\0';
+}