我无法弄清楚我的堆排序问题出在哪里。
该程序从命令行获取文件名,将单词导入向量,然后将该向量转换为向量对,vector<string,int>
其中 string 是单词,int 是该单词在文件中的实例数。
然后vector<PAIR>
按字符串(值或 v)或 int(键或 k)排序。我的按键排序工作正常,但按值排序已关闭。我怀疑我在按值排序时缺少 max_heapify 中的 if 语句。这是我的代码:
主文件
#include <fstream>
#include <iostream>
#include <stdlib.h>
#include <vector>
#include <string>
#include <string.h>
#include <stdio.h>
#include <map>
#include <time.h>
#include "readwords.h"
using namespace std;
readwords wordsinfile;
vector<string> allwords;
bool times;
char *filename;
timespec timestart,timeend;
vector< pair<string,int> > allwords_vp;
timespec diffclock(timespec start, timespec end);
int main ( int argc, char *argv[] ) {
filename = argv[1];
//Lets open the file
ifstream ourfile2(filename);
//Lets get all the words using our requirements
allwords = wordsinfile.getwords(ourfile2);
//Convert all the words from file and count how many times they
//appear. We will store them in a vector<string,int> string
//being the word and int being how many time the word appeared
allwords_vp = wordsinfile.count_vector(allwords);
cout << "HeapSort by Values" << endl;
if (times) {
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, ×tart);
wordsinfile.heapsort(const_cast<char *>("v"));
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timeend);
cout << "HeapSort by Values ran in "
<< diffclock(timestart,timeend).tv_nsec << " nanosecond or "
<< diffclock(timestart,timeend).tv_nsec/1000 << " millisecond"
<< endl;
} else {
wordsinfile.heapsort(const_cast<char *>("v"));
}
cout << "HeapSort by Keys" << endl;
if (times) {
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, ×tart);
wordsinfile.heapsort(const_cast<char *>("k"));
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timeend);
cout << "HeapSort by Keys ran in "
<< diffclock(timestart,timeend).tv_nsec << " nanosecond or "
<< diffclock(timestart,timeend).tv_nsec/1000 << " millisecond"
<< endl;
} else {
wordsinfile.heapsort(const_cast<char *>("k"));
}
}
timespec diffclock(timespec start, timespec end) {
timespec temp;
if ((end.tv_nsec-start.tv_nsec)<0) {
temp.tv_sec = end.tv_sec-start.tv_sec-1;
temp.tv_nsec = 1000000000+end.tv_nsec-start.tv_nsec;
} else {
temp.tv_sec = end.tv_sec-start.tv_sec;
temp.tv_nsec = end.tv_nsec-start.tv_nsec;
}
return temp;
}
读字.h
#ifndef READWORDS_H
#define READWORDS_H
#include <vector>
#include <map>
#include <utility>
#include <time.h>
typedef std::pair<std::string, int> PAIR;
bool isasciifile(std::istream& file);
class readwords {
private:
std::vector<PAIR> vp;
public:
std::vector<std::string> getwords(std::istream& file);
std::vector<PAIR> count_vector(std::vector<std::string> sv);
void print_vectorpair(std::vector<PAIR> vp);
void print_vector(std::vector<std::string> sv);
void heapsort(char how[]);
void buildmaxheap(std::vector<PAIR> &vp, int heapsize, char how[]);
void max_heapify(std::vector<PAIR> &vp, int i, int heapsize, char how[]);
void swap_pair(PAIR &p1, PAIR &p2);
};
读字.cpp
#include <fstream>
#include <iostream>
#include <map>
#include "readwords.h"
#include <vector>
#include <string>
#include <utility>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
//using std::vector;
using namespace std;
typedef pair<string, int> PAIR;
// Do we have a ASCII file?
// Lets test the second 10 chars to make sure
// This method is flawed if the file is less than 10 chars
bool isasciifile(std::istream& file) {
int c = 0;
bool foundbin = false;
for(c=0; c < 10;c++) {
if(!isprint(file.get())){
// Looks like we found a non ASCII file, or its empty.
foundbin = true;
}
}
return foundbin;
}
// This is our workhorse as it splits up the words based on our criteria and
// passes them back as a vector of strings.
vector<string> readwords::getwords(std::istream& file) {
char c;
string aword;
vector<string> sv;
//Let go through the file till the end
while(file.good()) {
c = file.get();
if (isalnum(c)) {
//convert any uppercase to lowercase
if(isupper(c)) {
c = (tolower(c));
}
//if its a space lets go onto the next char
if(isspace(c)) { continue; }
//everything looks good lets add the char to our word
aword.insert(aword.end(),c);
} else {
//its not a alphnum or a space so lets skip it
if(!isspace(c)) { continue; }
//reset our string and increment
if (aword != "") {sv.push_back(aword);}
aword = "";
continue;
}
}
return sv;
}
vector<PAIR> readwords::count_vector(vector<string> sv) {
unsigned int i = 0;
int j = 0;
int match = 0;
// cout << "Working with these string: " << endl;
// print_vector(sv);
for (i=0; i < sv.size(); i++) {
// cout << "count of i: " << i << " word is: " << sv.at(i) << endl;
match = 0;
if(readwords::vp.size() == 0) {
readwords::vp.push_back(make_pair(sv.at(i),1)); continue;
}
for (j=readwords::vp.size() - 1; j >= 0; --j) {
if (sv.at(i) == readwords::vp.at(j).first) {
// cout << "Match found with: " << sv.at(i) << endl;;
readwords::vp.at(j).second = readwords::vp.at(j).second + 1;
match = 1;
}
// cout << "Value of j and match: " << j << match << endl;
if ( j == 0 && match == 0) {
// cout << "Match found at end with: " << sv.at(i) << endl;;
readwords::vp.push_back(make_pair(sv.at(i),1));
}
}
}
//Prob need to sort by first data type then second here, prior to sort functions.
//Might not be the best place as the sort functions would alter it, if not here
//then each sort requires to do secondary search
return readwords::vp;
}
void readwords::print_vectorpair(vector<PAIR> vp) {
unsigned int i = 0;
for (i=0; i < vp.size(); ++i) {
cout << vp.at(i).first << " " << vp.at(i).second << endl;
}
}
void readwords::print_vector(vector<string> sv) {
unsigned int i = 0;
for (i=0; i < sv.size(); ++i) {
cout << sv.at(i) << endl;
}
}
void readwords::heapsort(char how[]) {
int heapsize = (readwords::vp.size() - 1);
buildmaxheap(readwords::vp, heapsize, how);
for(int i=(readwords::vp.size() - 1); i >= 0; i--) {
swap(readwords::vp[0],readwords::vp[i]);
heapsize--;
max_heapify(readwords::vp, 0, heapsize, how);
}
print_vectorpair(readwords::vp);
}
void readwords::buildmaxheap(vector<PAIR> &vp, int heapsize, char how[]) {
for(int i=(heapsize/2); i >= 0 ; i--) {
max_heapify(vp, i, heapsize, how);
}
}
void readwords::max_heapify(vector<PAIR> &vp, int i, int heapsize, char how[]) {
int left = ( 2 * i ) + 1;
int right = left + 1;
int largest;
if(!strcmp(how,"v")) {
if(left <= heapsize && vp.at(left).second >= vp.at(i).second ) {
if( vp.at(left).first >= vp.at(i).first ) {
largest = left;
} else {
largest = i;
}
} else {
largest = i;
}
if(right <= heapsize && vp.at(right).second >= vp.at(largest).second) {
if( vp.at(right).first >= vp.at(largest).first) {
largest = right;
}
}
}
if(!strcmp(how,"k")) {
if(left <= heapsize && vp.at(left).first > vp.at(i).first) {
largest = left;
} else {
largest = i;
}
if(right <= heapsize && vp.at(right).first > vp.at(largest).first) {
largest = right;
}
}
if(largest != i) {
swap(vp[i], vp[largest]);
max_heapify(vp, largest, heapsize, how);
}
}