c++ - How to read a string file from second line in C? -

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this code reads characters in file , calculates length of characters. how can read second line , ignore read first line?

this part of code:

    int lena = 0;     file * filea;     char holder;     char *seqa=null;     char *temp=null;      filea=fopen("d:\\str1.fa", "r");     if(filea == null) {     perror ("error opening 'str1.fa'\n");     exit(exit_failure);     }      while((holder=fgetc(filea)) != eof) {     lena++;     temp=(char*)realloc(seqa,lena*sizeof(char));     if (temp!=null) {         seqa=temp;         seqa[lena-1]=holder;     }     else {         free (seqa);         puts ("error (re)allocating memory");         exit (1);     } } cout<<"length seqa is: "<<lena<<endl; fclose(filea);

make counter of how many \n have seen,and when ==1 goto read 2nd line.

    int line=0;     while((holder=fgetc(filea)) != eof) {      if(holder == '\n') line++;      if(holder == 1) break; /* 1 because count start 0,you know */     }     if(holder == eof) {      //error:there's no 2nd     }           while((holder=fgetc(filea)) != eof) {      // holder contents begging 2nd line    }

you can make more simple using fgets():

make 1 call , ignore it(by don't discard result-value,for error-checking);

make second call, , begging reading this.

note: i'm considering c language here.


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