Need some String Help

I am trying to name a text file, but i need to name it something that varies.

INPUTread = fopen("Type I-A.txt", "r");

How can I name the file = m_somevariablenum " Type I-A.txt" so that it would look somthing like this "399 Type I-A.txt"


Thanks,

Code:

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char filename[128];
FILE *out;
int value;
value = 128;
sprintf (filename,"%d Type I-A.txt", value);
out=fopen(filename,"w");

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