How to make a random array to not repeat?

• February 17th, 2013, 07:29 AM
blackseed32
How to make a random array to not repeat?
Here is my code for a simple game. paste it and try it.

#include <iostream>
#include <string>
#include <ctime>
#include <cstdlib>
using namespace std;

int main (void)
{
string g[4],
b[4],
a[4],
l[4];

srand((unsigned int)time(0));

cout << "Welcome!\n\n";
cout << "Type 4 girl names.\n";
for (int gi = 0; gi < 4; gi++)
cin >> g[gi];

cout << "Type 4 boy names.\n";
for (int bi = 0; bi < 4; bi++)
cin >> b[bi];

cout << "\nWhat they do (enter 4 actions)?\n";
for (int ai = 0; ai < 4; ai++)
getline(cin, a[ai]);

cout << "\nWhere is happening (enter 4 locations)?\n";
for (int li = 0; li < 4; li++)
getline(cin, l[li]);

for (int c = 0; c < 4; c++)
cout << g[rand() % 4] << " and " << b[rand() % 4] << " are " << a[rand() % 4] << " from a " << l[rand() % 4] << endl;

return (0);
}

At the end in the 4 lines some of the names, actions and locations repeat. How do I make them to not repeat and use every name that you will enter? do I need random_shuffle? How can I integrate it in my code?
• February 17th, 2013, 08:20 AM
Philip Nicoletti
Re: How to make a random array to not repeat?
You can use random_shuffle ...

Code:

```#include <algorithm> // after entering the data ... random_shuffle(g,g+4); random_shuffle(b,b+4); random_shuffle(a,a+4); random_shuffle(l,l+4); for (int c = 0; c < 4; c++) {  cout << g[c] << " and " << b[c] << " are " << a[c] << " from a " << l[c] << endl; }```
Also, there is a bug when entering the data. It happens when you use operator >>
followed by getline() [ a google search should describe the problem in detail ].

Between the operator >> and the getline(), use the ignore() function:

Code:

``` cin >> b[bi];  cin.ignore(10000,'\n');```