求0?7所能組成的奇數個數

程序源代碼： main() { long sum=4,s=4; int j; for(j=2;j<=8;j++)/*j is place of number*/ { printf("\n%ld",sum); if(j<=2) s*=7; else s*=8; sum+=s;} printf("\nsum=%ld",sum); } *