Structure vector sorting in C + +

Once the header file include # <algorithm> is included, a vector can be sorted directly using the Sort function:

1 //Sort Algorithm Example2#include <iostream>//Std::cout3#include <algorithm>//Std::sort4#include <vector>//std::vector5   6 BOOLMyFunction (intIintj) {return(i<j); }  7   8 structMyClass {9   BOOL operator() (intIintj) {return(i<j);} Ten } MyObject;  One    A intMain () { -   intMyints[] = { +, in, A, $, -, the, -, -};  -std::vector<int> Myvector (myints, myints+8);// All in all the    -   //using default comparison (operator <): -Std::sort (Myvector.begin (), Myvector.begin () +4);//(a) -    +   //using function as comp -Std::sort (Myvector.begin () +4, Myvector.end (), myfunction);//(+) +    A   //using object as Comp atStd::sort (Myvector.begin (), Myvector.end (), MyObject);//(a) -    -   //Print out content: -Std::cout <<"Myvector contains:";  -    for(std::vector<int>::iterator It=myvector.begin (); It!=myvector.end (); ++it) -Std::cout <<' '<< *it;  inStd::cout <<'\ n';  -    to   return 0;  +}

But when a variable in a vector is a struct and needs to be sorted by one of the elements of the struct, some modification is required:

1#include"PrivateHeader.h"2#include <string>3#include <vector>4#include <iostream>5#include <algorithm>6 usingSTD::string;7 usingstd::vector;8 usingstd::cout;9 usingStd::endl;Ten using namespacestd; One  Atypedefstruct - { -     floatscore; the     stringfile_name; -     stringAll_file_name; -  - }tfileprop; +  - BOOLGreatersort (Tfileprop A, tfileprop b) + {  A     return(A.score >b.score); at } - BOOLLesssort (Tfileprop A, tfileprop b) - {  -     return(A.score <b.score); - } -Vector<tfileprop>Vecfileprop; in  -Vecfileprop.push_back (Tfileprop);//push operations on vectors to  +Std::sort (Vecfileprop.begin (), Vecfileprop.end (), greatersort);//sort in descending order -Std::sort (Vecfileprop.begin (), Vecfileprop.end (), lesssort);//sort in ascending order

Also, when using Iang to pass a parameter data, because the command line receives the parameters are stored in char** argv, so you need to cast first, after a string as the intermediate conversion variable, and finally into the int type, in addition, I think because it is a char type of reason, It should be possible for the master to pass 0-255 of arguments, but it is not right to think about it, because no matter how large the number is, it is passed in a string, and then the string type is forced to turn to the int type, so there is no size limit of 256.

1 intMainintargcChar**argv)2 {3     //Statistical Time4     //timestatistics ();5 6     //all results are placed in a folder display7     8     intNum_save;9     if(ARGC = =2)Ten     { OneSTD::stringThres = argv[1]; ANum_save =atof (Thres.c_str ()); -         //std::cout << "(int) argv[1] is" << argv[1]; -         //std::cout << "Num_save is" << num_save; the     } -     Else -     { -Num_save = -; +     } - Showallresult (num_save); +      A      at     return 1; -}

Reference: http://blog.csdn.net/zhouxun623/article/details/49887555

Structure vector sorting in C + +