exercism-solutions/cpp/beer-song/beer_song.cpp

64 lines
1.1 KiB
C++

#include "beer_song.h"
#include <cassert>
#include <cctype>
namespace beer {
using namespace std;
namespace {
string count_bottles(int count)
{
if (0 == count)
return "no more bottles";
if (1 == count)
return "1 bottle";
return to_string(count) + " bottles";
};
void capitalize_first(string &str)
{
assert(!str.empty());
str.front() = toupper(str.front());
};
}
string verse(int index)
{
string result = count_bottles(index)
+ " of beer on the wall, "
+ count_bottles(index)
+ " of beer.\n"
+ (index ? string("Take ")
+ (index == 1 ? "it" : "one")
+ " down and pass it around, "
: string("Go to the store and buy some more, "))
+ count_bottles(index ? index - 1 : 99)
+ " of beer on the wall.\n";
capitalize_first(result);
return result;
}
string sing(int from_index, int to_index)
{
string result;
assert(from_index >= to_index);
for (int i = from_index; i >= to_index; --i) {
result += (i == from_index ? "" : "\n");
result += verse(i);
}
return result;
}
}