Initial commit of code for dopelib, and ch 1, 2, and 12

libs/chapter1/check_permutation.cpp

@@ -0,0 +1,35 @@
+#include <iostream>
+#include <string>
+#include "chapter1.hpp"
+
+/* Prompt
+   Check Permutation: Given two strings, write a method to decide if
+   one is a permutation of the other.
+ */
+
+bool CheckPermutation(const char* s1, const char* s2,
+                      size_t s1_len, size_t s2_len){
+
+  int letters1[255] = {};
+  int letters2[255] = {};
+  long unsigned int indx = 0;
+
+  if(s1_len != s2_len){
+    return false;
+  }
+
+  for(indx = 0; indx < s1_len; ++indx){
+    int li1 = static_cast<int>(s1[indx]);
+    int li2 = static_cast<int>(s2[indx]);
+    letters1[li1] += 1;
+    letters2[li2] += 1;
+  }
+
+  for(indx = 0; indx < 255; ++indx){
+    if (letters1[indx] != letters2[indx]){
+      return false;
+    }
+  }
+
+  return true;
+}