我差不多完成了我的练习计划，但我仍然坚持将用户输入存储在一个未指定大小的数组中。
请查看我的代码：
#include <iostream>
#include <stdlib.h>
#include <string>
#include <ctype.h>
#include <cstring>
using namespace std;
int main() {
string items[9][3] = {{"A","BALOT","25.00"},
{"B","CANTON","20.00"},
{"C","NIDO","100.00"},
{"D","KETCHUP","50.00"},
{"E","MAGGI","15.00"},
{"F","ALASKA","60.00"},
{"G","VINEGAR","25.00"},
{"H","OIL","70.00"},
{"I","COKE","10.00"}};
// PARA MAPRINT YUNG ARRAY.
cout << "MANG JUAN'S 10-DAHAN\n\n";
for (int i = 0; i < 9; i++) {
for (int j = 0; j < 3; j++)
cout << items[i][j] << ( (j < 2) ? "-" : "\t" );
if (i < 6) {
cout << "\t";
i += 2;
}
else if (i != 8) {
cout << "\n";
i -= 6;
}
} // END OF ARRAY PRINTING
char choice, addAnother;
int ctr = 1, quantity = 0;
string purchased;
double price = 0, grandTotal = 0, total = 0;
cout << "\n\nWOULD YOU LIKE TO PURCHASE? Y/N\n\n";
cin >> choice;
if(choice == 'n' || choice == 'N') {
cout << "THANK YOU.";
}
else if(choice == 'y' || choice == 'Y') {
string numPref;
while (true) {
if(ctr > 11) {
cout << "\n\nTHE SYSTEM EXCEEDED ITS LIMIT\n\n";
break;
} else {
if(ctr == 1) numPref = "st";
else if(ctr == 2) numPref = "nd";
else if(ctr == 3) numPref = "rd";
else if(ctr > 3) numPref = "th";
}
//rows:
//for(int r = 0; r < 9; r++) {
cout << "\n\nPLEASE ENTER " << ctr << numPref << " ITEM:\t";
cin >> purchased;
char upp = purchased[0];
upp = toupper(upp);
purchased = upp;
if(!cin) {
cout << "Letters only";
break;
} else {
if(true) {
cout << "HOW MANY? ";
cin >> quantity;
if(!cin) {
cout << "Enter number only. ";
break;
} else {
cout << "PRICE PER ITEM: ";
///////// Look for the element and print the entire row /////////////
string *matchedRow;
const int length = 9;
for (int i = 0; i < 9; i++) {
string *oneRow = items[i];
/**if (oneRow[0] != purchased) {
cout << "\n\nNO ITEM FOUND!\n\n";
ctr--;
} else {
matchedRow = oneRow;
cout << matchedRow[2];
price = atof( matchedRow[2].c_str() );
total = price * quantity;
grandTotal += total;
} */
if(oneRow[0] == purchased) {
matchedRow = oneRow;
cout << matchedRow[2];
price = atof( matchedRow[2].c_str() );
total = price * quantity;
grandTotal += total;
if(oneRow[0] != purchased) {
cout << "NO MATCH FOUND!" << endl;
ctr--;
break;
}
}
} // End of for-loop for *matchedrow
////////////////////////////////////////////
cout << "\n\nADD ANOTHER ITEM? Y/N " << endl;
cin >> addAnother;
if(addAnother == 'y' || addAnother == 'Y') {
ctr++;
} else if(addAnother == 'n' || addAnother == 'N') {
// print the receipt here
goto receipt;
//break; // replace break with goto later
} else {
cout << "\n\nINVALID INPUT." << endl;
break;
} // End of if and else for addANother
}
} // end of else - if (!cin) for quantity input check
} // end of char check
//} // End of else for (!cin) //spare bracket
} // End of while-loop for numPref
//} // end of rows for-loop
} // End of else if (choice)
receipt:
cout << "YOUR PURCHASE:" << endl;
cout << "NET TOTAL: " << grandTotal << endl;
system("PAUSE");
//return 0;
}
我想输出购买摘要，例如此示例运行：
WOULD YOU LIKE TO PURCHASE? Y
PLEASE ENTER 1st ITEM: A
HOW MANY? 2
PRICE PER ITEM: 25.00
ADD ANOTHER? Y
PLEASE ENTER 2nd ITEM: B
HOW MANY? 1
PRICE PER ITEM: 20.00
ADD ANOTHER? N
YOUR PURCHASE:
// will display all the ordered item
// sample output
A BALOT 50.00
B CANTON 20.00
NET TOTAL: 70.00
答案 0 :(得分：0)
您不能拥有未指定大小的数组。请改用vector，例如：
#include<vector>
...
vector<string> user_inputs;
string purchased;
cin >> purchased;
user_inputs.push_back(purchased); //adding to vector
然后你可以收回你的意见：
for (int j = 0; j < user_inputs.size(); j++)
cout << user_inputs[j];
答案 1 :(得分：0)
- 如有人提到，此处需要abstraction，但如果您愿意，可以选择实施
#include <deque>
#include <string>
#include <iostream>
#include <limits>
#include <cstdlib>
#include <iomanip>
#include <cctype>
using std::cout;
using std::endl;
using std::cin;
using std::string;
typedef std::deque<string> dstr;
typedef std::deque<dstr> ddstr;
struct purchase_index {
string name;
double amt;
struct purchase_index *next;
} purchases;
const char *prefix[] = {"st", "nd", "rd", "th"};
int query( const unsigned );
void print_options(ddstr &);
unsigned add_purchase( purchase_index *, ddstr & );
void clrscr();
void print_purchase_hist(struct purchase_index *, char = '$');
int main() {
ddstr items = {{"A","BALOT","25.00"},
{"B","CANTON","20.00"},
{"C","NIDO","100.00"},
{"D","KETCHUP","50.00"},
{"E","MAGGI","15.00"},
{"F","ALASKA","60.00"},
{"G","VINEGAR","25.00"},
{"H","OIL","70.00"},
{"I","COKE","10.00"}
};
struct purchase_index *ptr = &purchases;
unsigned char prompt = 'y';
cout << "\n\nWOULD YOU LIKE TO PURCHASE? ";
int purchase(1);
while ( (cin >> prompt) and (prompt|32) == 'y' ) {
print_options(items);
if ( !query(purchase) ) break;
else if ( add_purchase(ptr, items) ) {
purchase++;
ptr = (ptr->next = new struct purchase_index());
}
cout << "ADD ANOTHER? ";
}
print_purchase_hist(&purchases);
return 0;
}
void print_purchase_hist(struct purchase_index *hist, char currency) {
cout << "\n\nYOUR PURCHASE:\n";
struct purchase_index *ptr = hist;
while (ptr->next != NULL){
cout << ptr->name << "\t" << currency << ptr->amt << '\n';
ptr = ptr->next;
}
}
inline void clrscr() {
cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
cout << std::setfill('\n') << std::setw(2) << '\n';
}
unsigned add_purchase( purchase_index *ptr, ddstr &itm ) {
unsigned char w;
unsigned num, index, ret(1);
if ( !(cin >> w) or (index = (toupper(w) - 65)) >= itm.size() ) {
cout << "NO MATCH FOUND!\n";
ret = 0;
}
else if ( cout << "HOW MANY? " and !(cin >> num) ) {
cout << "Enter Numbers only.\n";
ret = 0;
}
else {
ptr->name = itm[index][0] + "\t" + itm[index][1];
ptr->amt = (double)num * atof(itm[index][2].c_str());
}
clrscr();
return ret;
}
void print_options(ddstr &ref) {
cout << "Items you can purchase:\n";
for ( auto desc: ref ) {
cout << "\t";
for ( auto spec: desc )
cout << spec << " ";
cout << endl;
}
}
int query( const unsigned item_list ) {
if ( item_list > 11 ) {
cout << "\n\nTHE SYSTEM EXCEEDED ITS LIMIT\n\n";
return 0;
}
unsigned last = item_list % 10;
cout << "PLEASE ENTER THE " << item_list
<< ( last == 0 || last > 3 ? prefix[3] : prefix[last-1] )
<< " ITEM: ";
return 1;
}
WOULD YOU LIKE TO PURCHASE? y
Items you can purchase:
A BALOT 25.00
B CANTON 20.00
C NIDO 100.00
D KETCHUP 50.00
E MAGGI 15.00
F ALASKA 60.00
G VINEGAR 25.00
H OIL 70.00
I COKE 10.00
PLEASE ENTER THE 1st ITEM: e
HOW MANY? 3
ADD ANOTHER? y
Items you can purchase:
A BALOT 25.00
B CANTON 20.00
C NIDO 100.00
D KETCHUP 50.00
E MAGGI 15.00
F ALASKA 60.00
G VINEGAR 25.00
H OIL 70.00
I COKE 10.00
PLEASE ENTER THE 2nd ITEM: c
HOW MANY? 5
ADD ANOTHER? n
YOUR PURCHASE:
E MAGGI $45
C NIDO $500