"Excel Sheet Column Number"

Author: lennylxx

README.md

@@ -23,7 +23,7 @@ them with C++ Language.
 | 174 | [Dungeon Game]                                               |                    |
 | 173 | [Binary Search Tree Iterator]                                |                    |
 | 172 | [Factorial Trailing Zeroes]                                  | [C](src/172.c)     |
-| 171 | [Excel Sheet Column Number]                                  |                    |
+| 171 | [Excel Sheet Column Number]                                  | [C](src/171.c)     |
 | 170 | [Two Sum III - Data structure design]                        |                    |
 | 169 | [Majority Element]                                           | [C](src/169.c)     |
 | 168 | [Excel Sheet Column Title]                                   | [C](src/168.c)     |

src/171.c

@@ -0,0 +1,23 @@
+#include <stdio.h>
+#include <string.h>
+
+int titleToNumber(char *s) {
+    int len = strlen(s);
+    int i = 0;
+    int ans = 0;
+    while (i < len) {
+        ans = ans * 26 + s[i] - 'A' + 1;
+        i++;
+    }
+    
+    return ans;
+}
+
+int main() {
+    char s1[] = "Z";
+    char s2[] = "AB";
+    
+    printf("%d\n", titleToNumber(s1));
+    printf("%d\n", titleToNumber(s2));
+    return 0;
+}