Last active
August 29, 2015 13:57
-
-
Save bzar/9531212 to your computer and use it in GitHub Desktop.
Reaktor fast track outrun C++ solution
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
// g++ -Ofast -fomit-frame-pointer -funroll-loops -o reaktor_outrun reaktor_outrun.cpp | |
#include <iostream> | |
#include <vector> | |
#include <algorithm> | |
#include <limits> | |
#include <cctype> | |
#include <cstdio> | |
int main(int argc, char** argv) | |
{ | |
std::vector<unsigned int> buffers[2]; | |
std::vector<unsigned int>* curr = &buffers[0]; | |
std::vector<unsigned int>* prev = &buffers[1]; | |
curr->reserve(100); | |
prev->reserve(100); | |
unsigned int k = 0; | |
unsigned int i = 0; | |
unsigned int v = 0; | |
char c = '\0'; | |
bool inValue = false; | |
std::FILE* file = std::fopen(argv[1], "r"); | |
// Ignore first line seed comment | |
while(!std::feof(file) && std::getc(file) != '\n'); | |
int const BUF_SIZE = 1024 * 1024; | |
char buf[BUF_SIZE] = {0}; | |
std::size_t bufCount = 1; | |
std::size_t bufIndex = 0; | |
while(bufCount != 0) | |
{ | |
bufCount = std::fread(buf, sizeof(buf[0]), BUF_SIZE, file); | |
bufIndex = 0; | |
while(bufIndex < bufCount) | |
{ | |
c = buf[bufIndex]; | |
++bufIndex; | |
if(std::isdigit(c)) | |
{ | |
v = v * 10 + (c - '0'); | |
inValue = true; | |
continue; | |
} | |
else if(!inValue) | |
{ | |
continue; | |
} | |
if(i == k) | |
{ | |
i = 0; | |
k += 1; | |
std::vector<unsigned int>* temp = prev; | |
prev = curr; | |
curr = temp; | |
curr->push_back(0); | |
prev->push_back(0); | |
} | |
if(k > 1) | |
{ | |
if(i == 0) | |
{ | |
v += prev->at(0); | |
} | |
else if(i == k - 1) | |
{ | |
v += prev->at(k - 2); | |
} | |
else | |
{ | |
v += prev->at(i) > prev->at(i - 1) ? prev->at(i) : prev->at(i - 1); | |
} | |
} | |
curr->at(i) = v; | |
++i; | |
v = 0; | |
inValue = false; | |
} | |
} | |
int max = *std::max_element(curr->begin(), curr->end()); | |
std::cout << max << std::endl; | |
return 0; | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment