我正在用 C++ 编写一个数据结构程序，但令人惊讶的是，该结构并不是我悲伤的原因。在我下面发布的程序中，我有两个 else if 语句即使满足它们的条件也不会显示在我的输出中。他们是
else if (response == n)
cout << "Thank you, goodbye" << endl;
和
else if (response ==n)
cout << "\n" << endl
这就是全部
// array of structures
#include <iostream>
#include <string>
#include <sstream>
using namespace std;
#define NUM_MOVIES 6
//structure
struct movies_iit{
string title;
int year;
} films [NUM_MOVIES];
//global variables
char title [20];
int y = 1, n = 0, year;
string search;
//function 1
void sort_on_title(movies_iit films[], int n)
{
//Local struct variable used to swap records
movies_iit temp;
for(int i=0; i<n-1; i++)
{
for(int i=0; i<n-1; i++)
{
/*If s[i].title is later in alphabet than
s[i+1].title, swap the two records*/
if(films[i].title>films[i+1].title)
{
temp = films[i];
films[i] = films[i+1];
films[i+1] = temp;
}
}
}
}
//end function 1
//function query1 prototype
void query1 (movies_iit movie);
//function query2 prototype
void query2 (movies_iit movie);
//function 2 prototype
void printmovie (movies_iit movie);
//beginning of main
int main ()
{
string mystr;
int n;
char response;
for (n=0; n<NUM_MOVIES; n++)
{
cout << "Enter title: ";
getline (cin,films[n].title);
cout << "Enter year: ";
getline (cin,mystr);
stringstream(mystr) >> films[n].year;
}
//sort records, function 1 call
sort_on_title(films, NUM_MOVIES);
cout << "\nYou have entered these movies:\n";
for (n=0; n<NUM_MOVIES; n++)
printmovie (films[n]); //function 2 call
//Query 1
cout << "Perform an alphabetical search? (y/n)" << endl;
cin >> response;
if (response == y)
{
cout << "Please enter title" << endl;
cin >> title;
for (n=0; n<NUM_MOVIES; n++)
{
query1 (films[n]);
response == n;
}
}
else if (response == n)
cout << "\n" << endl;
else
cout << "invalid entry" << endl;
//Query 2
cout << "Perform a chronological search? (y/n)" << endl;
cin >> response;
//greater than
if (response == y)
{
cout << "greater than what year?" << endl;
cin >> year;
for (n=0; n<NUM_MOVIES; n++)
{
query2 (films[n]);
}
}
else if (response == n)
cout << "Thank you, goodbye." << endl;
else
cout << "invalid entry" << endl;
system("pause");
return 0;
}
//end of main
//function 2 definition
void printmovie (movies_iit movie)
{
cout << movie.title;
cout << " (" << movie.year << ")\n";
}
//function query1 defintion
void query1 (movies_iit movie)
{
if (movie.title == title)
{
cout << " >> " << movie.title;
cout << " (" << movie.year << ")\n";
}
else
{
cout << movie.title;
cout << " (" << movie.year << ")\n";
}
}
//function query2 definition
void query2 (movies_iit movie)
{
if (movie.year >= year)
{
cout << movie.title;
cout << " (" << movie.year << ")\n";
}
}
这个想法是制作一种电影的迷你数据库。除了 else if 语句似乎被忽略之外，该代码实际上运行良好。谁能解释为什么会这样？