Here this should work for you
#include <stdio.h>
int main(void)
{
char m[100];
int i;
for(i = 0; i < 5; i++)
{
if(i == 2)
m[i] = ' ';
else
m[i] = '0' + i; //<< Note ascii of 0 is 48
}
m[i]= '\0';
printf("%s",m);
return 0;
}