You can use "%02d" format
or don't use sprintf at all
Code:#include <string.h>
#include <stdio.h>
int main(int argc, char* argv[])
{
char modelName [] = "modelB.xx";
int len = strlen(modelName);
char a;
char b;
for(a='0';a<= '9'; a++)
{
for(b='0';b<='9';b+=5)
{
modelName[len-2] = a;
modelName[len-1] = b;
printf("%s\n",modelName);
}
}
return 0;
}