Longest commom prefix

Signed-off-by: Leo Ma <[email protected]>

014_longest_common_prefix/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test common_prefix.c

014_longest_common_prefix/common_prefix.c

@@ -0,0 +1,33 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+static char* longestCommonPrefix(char** strs, int strsSize)
+{
+    int i, capacity = 50, count = 0;
+    char *result = malloc(50);
+    bool go_on = true;
+    while (strsSize > 0 && go_on) {
+        char temp = strs[0][count];
+        for (i = 1; i < strsSize; i++) {
+            if (temp != strs[i][count]) break;
+        }
+        if (i == strsSize && temp != '\0') {
+            if (count + 1 + 1 >= capacity) {
+                capacity *= 2;
+                result = realloc(result, capacity + 1);
+            }
+            result[count++] = temp;
+        } else {
+            go_on = false;
+        }
+    }
+    result[count++] = '\0';
+    return result;
+}
+
+int main(int argc, char **argv)
+{
+    printf("%s\n", longestCommonPrefix(argv + 1, argc - 1));
+    return 0;
+}