Is there any alternative for 'substr()'?

Question

char patern[]="AGAAGAG";
int n = strlen(patern);
int pat[n];
for (int i = 0; i < n; i++)
{
    int j = 0;
    while(j <= i )
    {
        if (patern.substr(0, j) == patern.substr(i-j+1, j))
        {
            pat[i] = j;
        }
        j++;
    }
    cout<<pat[i]<<endl;
}

I can only use <iostream>, <cstring>, <cstdio>, <cstdlib>. The output is 0011232.

`char[]` doesn't have methods. Are you sure you're not using `std::string`? — Silvio Mayolo, Jun 02 '21 at 18:02
@SilvioMayolo if we change the first two line with string patern="AGAAGAG"; — zead seam, Jun 02 '21 at 18:12

score 1 · Answer 1 · answered Jun 02 '21 at 18:07

1

As character arrays do not have a method like substr then an alternative is using the C standard function strncmp declared in the header <cstring>. For example

if ( strncmp( patern, patern + i-j+1, j ) == 0 )

answered Jun 02 '21 at 18:07

Vlad from Moscow

301,070
26
186
335

I don't know how to than you really appreciate it – zead seam Jun 02 '21 at 18:11
3

@zeadseam thank people by upvoting and accepting their answer – Tim Randall Jun 02 '21 at 18:25

Is there any alternative for 'substr()'?

1 Answers1