leetcode

commit c145fbb0137e61d512e38acab0a9444b43943647
parent 935681b3ddd0cd9c2dc0a8b7a220969e270f3829
Author: Jack Sangdahl <jack@pngu.org>
Date:   Sun, 31 Aug 2025 08:24:57 -0600

500. keyboard row

Diffstat:
A
keyboard_row.c
 | 
50
++++++++++++++++++++++++++++++++++++++++++++++++++
A
keyboard_row.py
 | 
32
++++++++++++++++++++++++++++++++

2 files changed, 82 insertions(+), 0 deletions(-)
diff --git a/keyboard_row.c b/keyboard_row.c
@@ -0,0 +1,50 @@
+// 500. Keyboard Row
+#include "leetcode.h"
+
+/*
+ * given an array of strings 'words', return the words that can be typed using
+ * letters of the alphabet on only one row of american keyboard like the image
+ * below. note that the strings are case insensitive, both lowercased and
+ * uppercased of the same letter are treated as if they are at the same row.
+ */
+
+char **findWords(char **words, int wordsSize, int *returnSize) {
+  char **ans = (char **)malloc(wordsSize * sizeof(char *));
+  int idx = 0, lut[26] = {2, 3, 3, 2, 1, 2, 2, 2, 1, 2, 2, 2, 3,
+                          3, 1, 1, 1, 1, 2, 1, 1, 3, 1, 3, 1, 3};
+  bool same_line = true;
+  for (int i = 0; i < wordsSize; i++) {
+    same_line = true;
+    for (int j = 0; j < strlen(words[i]); j++) {
+      if (lut[(words[i][j] - 'A') % 32] != lut[(words[i][j + 1] - 'A') % 32]) {
+        same_line = false;
+        break;
+      }
+    }
+    if (same_line)
+      ans[idx++] = words[i];
+  }
+  *returnSize = idx;
+  return ans;
+}
+
+int main() {
+  char *w1[] = {"Hello", "Alaska", "Dad", "Peace"}, *w2[] = {"omk"},
+       *w3[] = {"adsdf", "sfd"};
+  int rs1, rs2, rs3;
+  char **fw1 = findWords((char **)w1, ARRAY_SIZE(w1), &rs1);
+  char **fw2 = findWords((char **)w2, ARRAY_SIZE(w2), &rs2);
+  char **fw3 = findWords((char **)w3, ARRAY_SIZE(w3), &rs3);
+  for (int i = 0; i < rs1; i++)
+    printf("%s ", fw1[i]); // expect: Alaska Dad
+  printf("\n");
+  for (int i = 0; i < rs2; i++)
+    printf("%s ", fw2[i]); // expect: omk
+  printf("\n");
+  for (int i = 0; i < rs3; i++)
+    printf("%s ", fw3[i]); // expect: adsdf sfd
+  printf("\n");
+  free(fw1);
+  free(fw2);
+  free(fw3);
+}
diff --git a/keyboard_row.py b/keyboard_row.py
@@ -0,0 +1,32 @@
+# 500. Keyboard Row
+
+"""
+given an array of strings 'words', return the words that can be typed using
+letters of the alphabet on only one row of american keyboard like the image
+below. note that the strings are case insensitive, both lowercased and
+uppercased of the same letter are treated as if they are at the same row.
+"""
+
+
+class Solution(object):
+    def findWords(self, words):
+        """
+        :type words: List[str]
+        :rtype: List[str]
+        """
+        l1 = set("qwertyuiop")
+        l2 = set("asdfghjkl")
+        l3 = set("zxcvbnm")
+        ans = []
+        for i in words:
+            curr = set(i.lower())
+            if curr <= l1 or curr <= l2 or curr <= l3:
+                ans.append(i)
+        return ans
+
+
+if __name__ == "__main__":
+    obj = Solution()
+    print(obj.findWords(words=["Hello", "Alaska", "Dad", "Peace"]))
+    print(obj.findWords(words=["omk"]))
+    print(obj.findWords(words=["adsdf", "sfd"]))