C 從鍵盤輸入一個整數，輸出對應的八進制和十六進制

#include <stdio.h>
int changebase(int number, int base);
int bitchangeradix(int i , int radix);
int main() {
    int number=0;
    scanf("%d",&number);
    printf("%o %x\n", number, number);
//    printf("%d %d\n", bitchangeradix(number,8), bitchangeradix(number,16));
    printf("%d %d", changebase(number,8),changebase(number, 16));
    return 0;
}
//changebase函數當number爲負數時陷入死循環
int changebase(int number, int base) {
    int a = 0;
    int i = 1;
    while (number) {
        int tmp = number % base;
        number /= base;
        tmp *= i;
        i *= 10;
        a += tmp;

    }
    return a;
}
int bitchangeradix(int i , int radix){
    int t ,step;
    if(radix==8)
     t=7,step=3;
    else if (radix==16)
         t=15,step=4;
    else
        return -1;
    int tmp=0;
    int ten=1;
    while (i){
        tmp+=(i&t)*ten;
        ten*=10;
        i=i>>step;
    }
    return tmp;
}

 

圖爲printf格式化輸出和bitchangeradix的結果
bitchangeradix函數思路是講二進制串 按照3個一組（八進制）看成一個十進制數來讀