strstr

6 files changed, 111 insertions, 4 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4782b07..7f2e354 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.8)
 project(advent-of-code LANGUAGES CXX)
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3 -Wall -Wextra -pedantic -Wno-unused-parameter")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3 -Wall -Wextra -pedantic -Wno-unused-parameter -Wno-sizeof-array-argument -Wno-sizeof-pointer-div")
 set(CMAKE_CXX_STANDARD 11)
 set(CMAKE_CXX_EXTENSIONS Off)
 
diff --git a/src/2015/day5/aoc.cpp b/src/2015/day5/aoc.cpp
index 1c33c66..d3f310b 100644
--- a/src/2015/day5/aoc.cpp
+++ b/src/2015/day5/aoc.cpp
@@ -1,5 +1,40 @@
 #include "aoc.h"
+#include <algorithm>
 
 namespace aoc2015 {
 
+int count_vowels(line_view lv, const char* vowels) {
+  ascii_count ac{lv};
+  int total = 0;
+  per_char(vowels, [&ac, &total](char c) {
+    total += ac[c];
+    return true;
+  });
+  return total;
 }
+
+bool is_nice(line_view lv, int repeated) {
+  const char* p = lv.line;
+  while (p + repeated < lv.line + lv.length) {
+    if (is_repeated(p, p + repeated)) {
+      return true;
+    } else {
+      p++;
+    }
+  }
+  return false;
+}
+
+bool is_nice(line_view lv, const char* disallowed[]) {
+  size_t size = sizeof(disallowed) / sizeof(*disallowed);
+  if (std::any_of(disallowed, disallowed + size, [&lv](const char* s) -> bool { return lv.contains(s); })) {
+    return false;
+  }
+  return true;
+}
+
+/*
+int day5(line_view) {}
+*/
+
+} // namespace aoc2015
diff --git a/src/2015/day5/aoc.h b/src/2015/day5/aoc.h
index a0b442c..beaa278 100644
--- a/src/2015/day5/aoc.h
+++ b/src/2015/day5/aoc.h
@@ -3,9 +3,9 @@
 
 namespace aoc2015 {
 
-int count_vowels(line_view, char*);
-bool contains_repeated(line_view, int);
-bool has_no_disallowed(line_view, char*[]);
+int count_vowels(line_view, const char*);
+bool is_nice(line_view, int);
+bool is_nice(line_view, const char*[]);
 
 int day5(line_view);
 
diff --git a/src/common.cpp b/src/common.cpp
index 8442bf6..1342109 100644
--- a/src/common.cpp
+++ b/src/common.cpp
@@ -31,3 +31,14 @@ line_view next_line(line_view file, size_t* offset) {
   *offset = p2 - file.line + 1;
   return {p1, static_cast<size_t>(p2 - p1 + 1)};
 }
+
+bool is_repeated(const char* p1, const char* p2) {
+  char c = *p1;
+  while (p1 != p2) {
+    if (*p1 != c) {
+      return false;
+    }
+    p1++;
+  }
+  return true;
+}
diff --git a/src/common.h b/src/common.h
index 4b2683d..7f2dfc9 100644
--- a/src/common.h
+++ b/src/common.h
@@ -2,12 +2,15 @@
 
 #include <iostream>
 #include <stdlib.h>
+#include <string.h>
 #include <utility>
 
 struct line_view {
   const char* line;
   size_t length;
 
+  line_view(const char* s = nullptr) : line(s) { length = s == nullptr ? 0 : strlen(s); }
+  line_view(const char* s, size_t l) : line(s), length(l) {}
   friend std::ostream& operator<<(std::ostream& o, const line_view& lv) {
     for (size_t i = 0; i < lv.length; i++) {
       o << lv.line[i];
@@ -25,6 +28,22 @@ struct line_view {
     }
     return l[i] == '\0';
   }
+
+  bool contains(const char* s) {
+    size_t len = strlen(s);
+    const char* p = line;
+    while (p + len < line + length) {
+      if (*p == *s) {
+        line_view x{p, len};
+        if (x == s) {
+          return true;
+        } else {
+          p++;
+        }
+      }
+    }
+    return false;
+  }
 };
 
 line_view load_file(const char*);
@@ -41,3 +60,35 @@ void per_line(line_view file, F&& f, Args&&... args) {
     }
   } while (offset < file.length);
 }
+
+template <typename F, typename... Args>
+void per_char(line_view line, F&& f, Args&&... args) {
+  for (size_t i = 0; i < line.length; i++) {
+    if (!f(line.line[i], std::forward<Args>(args)...)) {
+      break;
+    }
+  }
+}
+
+struct ascii_count {
+  int count[256];
+
+  ascii_count(line_view lv) : count{0} {
+    per_char(lv, [this](char c) {
+      count[static_cast<int>(c)] += 1;
+      return true;
+    });
+  }
+
+  int operator[](char c) const noexcept { return count[static_cast<int>(c)]; }
+  friend std::ostream& operator<<(std::ostream& o, const ascii_count& ac) {
+    for (size_t i = 0; i < 256; i++) {
+      if (ac.count[i] > 0) {
+        o << i << " -> " << ac.count[i] << "\n";
+      }
+    }
+    return o;
+  }
+};
+
+bool is_repeated(const char* p1, const char* p2);
diff --git a/test/test_common.cpp b/test/test_common.cpp
index 851bef7..1486988 100644
--- a/test/test_common.cpp
+++ b/test/test_common.cpp
@@ -13,3 +13,13 @@ TEST_CASE("load file", "[]") {
       },
       lines);
 }
+
+TEST_CASE("char count", "[]") {
+  line_view line{"accad1\n", 7};
+  ascii_count ac{line};
+  REQUIRE(ac['\n'] == 1);
+  REQUIRE(ac['a'] == 2);
+  REQUIRE(ac['c'] == 2);
+  REQUIRE(ac['d'] == 1);
+  REQUIRE(ac['1'] == 1);
+}