我需要弄清楚如何阅读此文件：
48
0 3023 1942
1 6734 1453
2 2233 10
3 5530 1424
4 401 841
5 3082 1644
6 7608 4458
7 7573 3716
8 7265 1268
9 6898 1885
10 1112 2049
11 5468 2606
12 5989 2873
13 4706 2674
14 4612 2035
15 6347 2683
16 6107 669
17 7611 5184
18 7462 3590
19 7732 4723
20 5900 3561
21 4483 3369
22 6101 1110
23 5199 2182
24 1633 2809
25 4307 2322
26 675 1006
27 7555 4819
28 7541 3981
29 3177 756
30 7352 4506
31 7545 2801
32 3245 3305
33 6426 3173
34 4608 1198
35 23 2216
36 7248 3779
37 7762 4595
38 7392 2244
39 3484 2829
40 6271 2135
41 4985 140
42 1916 1569
43 7280 4899
44 7509 3239
45 10 2676
46 6807 2993
以下是我目前为.h文件提供的代码：
#pragma once
#include <string>
class TSP
{
public:
TSP(const double crossoverProbability, const double mutationProbability);
/* The constants used in this project */
static const unsigned int chromosones = 30, cities, xMin = 0, xMax = 1000, yMin = 0, yMax = 500;
/* Generate a random population of chromosones */
void randomPopulation();
/* Create a new population using crossover and mutation */
void nextPopulation();
/* Returns the fitness of the best chromosone */
double getBestFitness() const;
/* Returns a string representation of the best path */
std::string getBestPathString() const;
/* Returns the total distance of the best chromosone path */
double getLowestTotalDistance() const;
/* Returns the populations average length */
double getAverageDistance() const;
private:
const double crossoverProbability, mutationProbability;
/* Gets the total distance of the supplied path */
double totalDistance(int const * const chromosone) const;
/* The coordinates for each city, (x,y) for the first city is found in (citiesX[0], citiesY[0]) */
double citiesX[cities], citiesY[cities];
/* The chromosone containing the shortest path */
int *bestChromosone;
/* Contains the current population of chromosones */
int (* solutions)[cities],
/* The two chromosones with the best fitness functions */
//bestChromosone1[cities], bestChromosone2[cities],
/* Used to store the new chromosones when creating a new population */
(* newPopulation)[cities];
/* Returns a random double r, 0 <= r <= max */
static double randomInclusive(const double max);
/* Returns a random double r, 0 <= r < max */
static double randomExclusive(const double max);
/* True if the two chromosones represent the same path */
static bool areChromosonesEqual(int const * const chromosoneA, int const * const chromosoneB);
/* Evaluate the fitness the supplied chromosone */
double evaluateFitness(const int * const chromosone) const;
/* Selects a chromosone from the current population using Roulette Wheel Selection.*/
int * rouletteSelection(double const * const fitness) const;
/* Replace the element at offspringIndex with the first element found in other that does not exist in offspringToRepair */
void repairOffspring(int * const offspringToRepair, int missingIndex, const int * const other);
/* Might swap one gene with another, depending on the mutation probability */
void mutate(int * const chromosone);
/* Cross over the parents to form new offspring using Multi-Point Crossover, collisions are handled as shown in lecture 5.
* The chromosones might be a copy of their parents, depending on the crossover probability.
*/
void crossover(const int * const parentA, const int * const parentB, int * const offspringA, int * const offspringB);
/* Checks if the supplied chromosone is in newPopulation */
bool hasDuplicate(const int * const chromosone, size_t populationCount);
/* Copies the supplied chromosone to the new population */
void copyToNewPopulation(const int * const chromosone, size_t index);
/* Make the chromosone represent a path, which is chosen by random */
static void setRandomPath(int * const chromosone);
};
我试图找出如何读取文本文件中的第一个数字并将其放入上面代码中的“cities”变量中。我还需要将每行中的第一个数字（第一行之后）读入变量* bestChromosone。然后我需要将每行中的第二个数字放入citiesX []，并将每行中的第三个数字放入citiesY []。任何人都可以帮我这么做吗？
如果需要，.cpp文件如下：
#include "tsp.h"
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <cmath>
#include <iostream>
#include <cassert>
#include <algorithm>
#include <sstream>
#include <cstring>
#include <limits>
using namespace std;
TSP::TSP(double crossoverProbability, double mutationProbability) : crossoverProbability(crossoverProbability),
mutationProbability(mutationProbability), solutions(new int[chromosones][cities]), newPopulation(new int[chromosones][cities])
{
/* Seed the random number generator */
srand((unsigned int)time(NULL));
/* Use the same number to generate a specific sequence */
//srand(0);
/* Set random coordinates */
for(size_t coordinateIndex = 0; coordinateIndex < cities; ++coordinateIndex)
{
/* 0 <= x <= xMax */
citiesX[coordinateIndex] = randomInclusive(xMax);
/* 0 <= y <= yMax */
citiesY[coordinateIndex] = randomInclusive(yMax);
}
/* Generate random population */
randomPopulation();
}
void TSP::randomPopulation()
{
/* Iterate throught each chromosone... */
for(size_t chromosoneIndex = 0; chromosoneIndex < chromosones; ++chromosoneIndex)
{
/* ... and give it a random path */
setRandomPath(solutions[chromosoneIndex]);
}
}
double TSP::getBestFitness() const
{
return evaluateFitness(bestChromosone);
}
double TSP::getAverageDistance() const
{
double distance = 0;
for(size_t chromosoneIndex = 0; chromosoneIndex < chromosones; ++chromosoneIndex)
{
distance += totalDistance(solutions[chromosoneIndex]);
}
return distance/chromosones;
}
string TSP::getBestPathString() const
{
stringstream path;
for(size_t gene = 0; gene < cities; ++gene)
{
if(gene != 0)
{
path << ",";
}
path << bestChromosone[gene];
}
return path.str();
}
double TSP::getLowestTotalDistance() const
{
return totalDistance(bestChromosone);
}
void TSP::nextPopulation()
{
double fitness[chromosones];
/* Fill an array with a fitness score for each chromosone,
* the index of a score corresponds with the chromosone's index in solutions[index]
*/
for(size_t chromosoneIndex = 0; chromosoneIndex < chromosones; ++chromosoneIndex)
{
fitness[chromosoneIndex] = evaluateFitness(solutions[chromosoneIndex]);
}
/* Use elitism, find and copy over the two best chromosones to the new population */
int eliteIndex1 = 0, eliteIndex2 = 0;
/* find the best solution */
eliteIndex1 = max_element(fitness, fitness + chromosones) - fitness;
this->bestChromosone = solutions[eliteIndex1];
double highestFitness = 0;
/* Find the second best solution */
for(size_t chromosoneIndex = 0; chromosoneIndex < chromosones; ++chromosoneIndex)
{
if(chromosoneIndex != eliteIndex1 && fitness[chromosoneIndex] > highestFitness)
{
highestFitness = fitness[chromosoneIndex];
eliteIndex2 = chromosoneIndex;
}
}
/* Keep track of how many chromosones exists in the new population */
size_t offspringCount = 0;
/* Copy over the two best solutions to the new population */
copyToNewPopulation(solutions[eliteIndex1], offspringCount);
++offspringCount;
copyToNewPopulation(solutions[eliteIndex2], offspringCount);
++offspringCount;
/* Create the rest of the new population, break this loop when the new population is complete */
while(true)
{
int * parentA;
int * parentB;
parentA = rouletteSelection(fitness);
parentB = rouletteSelection(fitness);
while (parentB == parentA)
{
parentB = rouletteSelection(fitness);
}
int offspringA[cities];
int offspringB[cities];
crossover(parentA, parentB, offspringA, offspringB);
mutate(offspringA);
mutate(offspringB);
/* Add to new population if an equal chromosone doesn't exist already */
if(!hasDuplicate(offspringA, offspringCount))
{
copyToNewPopulation(offspringA, offspringCount);
++offspringCount;
}
/* We need to check if the new population is filled */
if(offspringCount == chromosones)
{
break;
}
if(!hasDuplicate(offspringB, offspringCount))
{
copyToNewPopulation(offspringB, offspringCount);
++offspringCount;
}
/* Check again so that we don't accidentaly write all over the heap and have to spend an evening wondering why the heap is corrupt... :) */
if(offspringCount == chromosones)
{
break;
}
}
/*
* We now have a new population,
* now it needs to replace the current population
* so that we don't go through the same population every time we run this function
*/
for(size_t chromosoneIndex = 0; chromosoneIndex < chromosones; ++chromosoneIndex)
{
memcpy(solutions[chromosoneIndex], newPopulation[chromosoneIndex], sizeof(int) * cities);
}
}
bool TSP::hasDuplicate(const int * const chromosone, size_t populationCount)
{
/* Iterate throught each chromosone in newPopulation and compare them gene by gene */
for(size_t chromosoneIndex = 0; chromosoneIndex < populationCount; ++chromosoneIndex)
{
int genesCompared = 0;
for(size_t gene = 0; gene < cities; ++gene)
{
if(chromosone[gene] != newPopulation[chromosoneIndex][gene])
{
/* These chromosones are not equal! */
break;
}
++genesCompared;
}
if(genesCompared == cities)
{
return true;
}
}
return false;
}
void TSP::mutate(int * const chromosone)
{
/* 0.0 <= random <= 1 */
{
double random = randomInclusive(1);
/* Nope, didn't happen */
if(random > mutationProbability)
{
return;
}
}
int tmp;
int random1 = (int)randomExclusive(cities);
int random2 = (int)randomExclusive(cities);
while(random1 == random2)
{
random2 = (int)randomExclusive(cities);
}
tmp = chromosone[random1];
chromosone[random1] = chromosone[random2];
chromosone[random2] = tmp;
}
void TSP::crossover(int const * const parentA, const int * const parentB, int * offspringA, int * offspringB)
{
{
/* There is a chance we don't perform a crossover,
* in that case the offspring is a copy of the parents
*/
/* 0.0 <= random <= 1 */
double random = randomInclusive(1);
/* The offspring is a copy of their parents */
if(random > crossoverProbability)
{
memcpy(offspringA, parentA, sizeof(int) * cities);
memcpy(offspringB, parentB, sizeof(int) * cities);
return;
}
}
/* Perform multi-point crossover to generate offspring */
/* 0 <= cuttOffIndex <= cities */
int cuttOffIndex1 = (int)randomInclusive(cities);
int cuttOffIndex2 = (int)randomInclusive(cities);
while(cuttOffIndex2 == cuttOffIndex1)
{
cuttOffIndex2 = (int)randomExclusive(cities);
}
unsigned int start;
unsigned int end;
if(cuttOffIndex1 < cuttOffIndex2)
{
start = cuttOffIndex1;
end = cuttOffIndex2;
}
else
{
start = cuttOffIndex2;
end = cuttOffIndex1;
}
/* Offspring A is initially copy of parent A */
memcpy(offspringA, parentA, sizeof(int) * cities);
/* Offspring B is initially copy of parent B */
memcpy(offspringB, parentB, sizeof(int) * cities);
/* Put a sequence of parent B in offspring A */
memcpy(offspringA + start, parentB + start, sizeof(int) * (end - start));
/* Put a sequence of parent A in offspring B */
memcpy(offspringB + start, parentA + start, sizeof(int) * (end - start));
/* Mark collisions in offspring with -1*/
for(size_t cityIndex = 0; cityIndex < cities; ++cityIndex)
{
/* Index is part of the parent sequence */
if((cityIndex >= start && cityIndex < end)) {
/* Do nothing, we want to keep this sequence intact */
}
else
{
/* Check if the item at cityIndex also occurs somewhere in the copied substring */
for(size_t substringIndex = start; substringIndex < end; ++substringIndex)
{
/* A duplicate, mark it */
if(offspringA[cityIndex] == offspringA[substringIndex])
{
offspringA[cityIndex] = -1;
}
if(offspringB[cityIndex] == offspringB[substringIndex])
{
offspringB[cityIndex] = -1;
}
}
}
}
/*
* Go through the offspring,
* if an element is marked we fill the hole with an element from the other offspring
*/
for(size_t offspringIndex = 0; offspringIndex < cities; ++offspringIndex)
{
/* There is a hole here */
if(offspringA[offspringIndex] == -1)
{
repairOffspring(offspringA, offspringIndex, offspringB);
}
if(offspringB[offspringIndex] == -1)
{
repairOffspring(offspringB, offspringIndex, offspringA);
}
}
}
void TSP::repairOffspring(int * const offspringToRepair, int missingIndex, const int * const other)
{
/* Iterate through the other offspring until we find an element which doesn't exist in the offspring we are repairing */
for(size_t patchIndex = 0; patchIndex < cities; ++patchIndex)
{
/* Look for other[patchIndex] in offspringToRepair */
int *missing = find(offspringToRepair, offspringToRepair + cities, other[patchIndex]);
/* The element at other[patchIndex] is missing from offspringToRepair */
if(missing == (offspringToRepair + cities))
{
//cout << "1:" << offspringToRepair[missingIndex] << endl;
offspringToRepair[missingIndex] = other[patchIndex];
//cout << "2:" << offspringToRepair[missingIndex] << endl;
break;
}
}
}
void TSP::copyToNewPopulation(int const * const chromosone, size_t index)
{
assert(index < chromosones && "Index out of bounds");
for(size_t i = 0; i < cities; ++i)
{
newPopulation[index][i] = chromosone[i];
}
}
int * TSP::rouletteSelection(double const * const fitness) const
{
double sum = 0;
/* Calculate sum of all chromosome fitnesses in population */
for(size_t i = 0; i < chromosones; ++i)
{
sum += fitness[i];
}
/* 0.0 <= random <= sum */
double random = randomInclusive(sum);
sum = 0;
/* Go through the population and sum fitnesses from 0 to sum s. When the sum s is greater or equal to r; stop and return the chromosome where you are */
for(size_t i = 0; i < chromosones; ++i)
{
sum += fitness[i];
if(sum >= random)
{
return solutions[i];
}
}
assert(false && "A chromosone should have been picked by now");
return(NULL);
}
void TSP::setRandomPath(int * chromosone)
{
for(size_t i = 0; i < cities; ++i)
{
chromosone[i] = i;
}
/*
* Shuffle the chromosone
*/
for(size_t i = cities-1; i > 0; --i)
{
/* 0 <= random <= i */
int random = (int)randomInclusive(i);
int temp = chromosone[i];
chromosone[i] = chromosone[random];
chromosone[random] = temp;
}
}
double TSP::evaluateFitness(int const * const chromosone) const
{
return 1/totalDistance(chromosone);
}
double TSP::totalDistance(int const * const chromosone) const
{
double distance = 0;
/* Calculate the total distance between all cities */
for(size_t i = 0; i < cities-1; ++i)
{
double dx = citiesX[chromosone[i]] - citiesX[chromosone[i+1]];
double dy = citiesY[chromosone[i]] - citiesY[chromosone[i+1]];
/* The distance between two points is the square root of (dx^2+dy^2) */
distance += sqrt((pow(dx, 2.0) + pow(dy, 2.0)));
}
/* We complete the tour by adding the distance between the last and the first city */
double dx = citiesX[chromosone[cities-1]] - citiesX[chromosone[0]];
double dy = citiesY[chromosone[cities-1]] - citiesY[chromosone[0]];
distance += sqrt((pow(dx, 2.0) + pow(dy, 2.0)));
return distance;
}
double TSP::randomInclusive(double max)
{
/* Generate random number r, 0.0 <= r <= max */
//return ((double)rand() / (double)RAND_MAX * max);
return ((double)rand() * max) / (double)RAND_MAX;
}
double TSP::randomExclusive(double max)
{
/* Generate random number r, 0.0 <= r < max */
//return ((double)rand() / ((double)RAND_MAX + 1) * max);
return ((double)rand() * max) / ((double)RAND_MAX + 1);
}
int main(int argc, const char *argv[])
{
/* 90% mutation probability, 2% mutation probability */
TSP *tsp = new TSP(0.9, 0.02);
size_t generations = 0, generationsWithoutImprovement = 0;
double bestFitness = -1;
double initialAverage = tsp->getAverageDistance();
/* We'll stop when we've gone 10k generations without improvement */
while(generationsWithoutImprovement < 10000)
{
tsp->nextPopulation();
++generations;
double newFitness = tsp->getBestFitness();
/* The new fitness is higher, the chromosone is better */
if(newFitness > bestFitness)
{
bestFitness = newFitness;
generationsWithoutImprovement = 0;
//cout << "Best goal function: " << tsp->getBestFitness() << endl;
}
else
{
++generationsWithoutImprovement;
}
}
//cout << "DONE!" << endl;
//cout << "Number of generations: " << generations << endl;
//cout << "Best chromosone info: " << endl;
cout << "\t-Path: " << tsp->getBestPathString() << endl;
//cout << "\t-Goal function: " << tsp->getBestFitness() << endl;
//cout << "\t-Distance: " << tsp->getLowestTotalDistance() << endl;
//cout << "Average distance: " << tsp->getAverageDistance() << endl;
//cout << "Initial average: " << initialAverage << endl;
delete tsp;
return 0;
}
答案 0 :(得分：1)
#include <iostream>
#include <iomanip> // for setw() and ws
#include <string>
#include <fstream>
#include <cstdlib>
#include<vector>
using namespace std;
/* function prototype(s) */
void solveit (ifstream&);
void addContents(ifstream&);
int main(int argc, char* argv[])
{
ifstream datafile {argv[1]}; /* first arg is filename */
addContents(datafile);
datafile.close();
return 0;
}
void addContents(ifstream& ff){
vector<int> xCord;
vector<int> yCord;
int xCurrentLine;
int yCurrentLine;
int cityNumber;
int numberCities;
ff >> numberCities;
for(int i = 0; i<numberCities; i++){
ff >> cityNumber;
ff >> xCurrentLine;
ff >> yCurrentLine;
//do whatever you wanted to do with cityNumber
xCord.push_back(xCurrentLine);
yCord.push_back(yCurrentLine);
}
for (int i = 0; i<xCord.size(); i++){
cout << xCord.at(i) << " " << yCord.at(i) << endl;
}
}
此示例使用向量