From 82dc7441133d28de257156df04f8c6e58b2b128d Mon Sep 17 00:00:00 2001
From: aedavelli <9965118+aedavelli@users.noreply.github.com>
Date: Thu, 5 Jul 2018 22:03:30 -0700
Subject: [PATCH] Added code to check permutation

---
 .../Q1_02_Check_Permutation/QuestionA.c       | 39 +++++++++++++++++++
 .../Q1_02_Check_Permutation/QuestionB.c       | 36 +++++++++++++++++
 2 files changed, 75 insertions(+)
 create mode 100644 Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionA.c
 create mode 100644 Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionB.c

diff --git a/Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionA.c b/Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionA.c
new file mode 100644
index 0000000..4ddef60
--- /dev/null
+++ b/Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionA.c	
@@ -0,0 +1,39 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MAX_TEST_STRING_SIZE 10
+
+static int cmpcharp(const void *p1, const void *p2) {
+  return *(char *)p1 - *(char *)p2;
+}
+
+static bool is_permutation(const char *s1, const char *s2) {
+  bool result = false;
+
+  char *word1copy = strdup(s1);
+  char *word2copy = strdup(s2);
+
+  qsort(word1copy, strlen(word1copy), sizeof(char), cmpcharp);
+  qsort(word2copy, strlen(word2copy), sizeof(char), cmpcharp);
+
+  result = strcmp(word1copy, word2copy) ? false : true;
+
+  /* Need to free as strdup allocated memory */
+  free(word1copy);
+  free(word2copy);
+
+  return result;
+}
+
+int main(int argc, char const *argv[]) {
+  char pairs[][2][MAX_TEST_STRING_SIZE] = {
+      {"apple", "papel"}, {"carrot", "tarroc"}, {"hello", "llloh"}};
+  int number_of_pairs = sizeof(pairs) / sizeof(pairs[0]);
+  for (int i = 0; i < number_of_pairs; ++i) {
+    printf("%s, %s : %s\n", pairs[i][0], pairs[i][1],
+           is_permutation(pairs[i][0], pairs[i][1]) ? "true" : "false");
+  }
+  return 0;
+}
\ No newline at end of file
diff --git a/Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionB.c b/Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionB.c
new file mode 100644
index 0000000..eb163f8
--- /dev/null
+++ b/Ch 01. Arrays and Strings/Q1_02_Check_Permutation/QuestionB.c	
@@ -0,0 +1,36 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+#define MAX_TEST_STRING_SIZE 10
+
+static bool is_permutation(const char *s1, const char *s2) {
+  char letters[128] = {0};
+
+  const char *tmp = s1;
+  while (*tmp) {
+    letters[(int)*tmp]++;
+    tmp++;
+  }
+
+  tmp = s2;
+  while (*tmp) {
+    letters[(int)*tmp]--;
+    if (letters[(int)*tmp] < 0) {
+      return false;
+    }
+    tmp++;
+  }
+  return true;
+}
+
+int main(int argc, char const *argv[]) {
+  char pairs[][2][MAX_TEST_STRING_SIZE] = {
+      {"apple", "papel"}, {"carrot", "tarroc"}, {"hello", "llloh"}};
+  int number_of_pairs = sizeof(pairs) / sizeof(pairs[0]);
+  for (int i = 0; i < number_of_pairs; ++i) {
+    printf("%s, %s : %s\n", pairs[i][0], pairs[i][1],
+           is_permutation(pairs[i][0], pairs[i][1]) ? "true" : "false");
+  }
+  return 0;
+}
\ No newline at end of file