int convertBinarytoOctal(long long binaryNumber);
int main()
{
long long binaryNumber;

printf("输入一个二进制数: ");
scanf("%lld", &binaryNumber);

printf("二进制数 %lld 转换为八进制为 %d", binaryNumber, convertBinarytoOctal(binaryNumber));

return 0;
}

int convertBinarytoOctal(long long binaryNumber)
{
int octalNumber = 0, decimalNumber = 0, i = 0;

while(binaryNumber != 0)
{
decimalNumber += (binaryNumber%10) * pow(2,i);
++i;
binaryNumber/=10;
}

i = 1;

while (decimalNumber != 0)
{
octalNumber += (decimalNumber % 8) * i;
decimalNumber /= 8;
i *= 10;
}

return octalNumber;
}

long long convertOctalToBinary(int octalNumber);
int main()
{
int octalNumber;

printf("输入一个八进制数: ");
scanf("%d", &octalNumber);

printf("八进制数 %d 转二进制为 %lld", octalNumber, convertOctalToBinary(octalNumber));

return 0;
}

long long convertOctalToBinary(int octalNumber)
{
int decimalNumber = 0, i = 0;
long long binaryNumber = 0;

while(octalNumber != 0)
{
decimalNumber += (octalNumber%10) * pow(8,i);
++i;
octalNumber/=10;
}

i = 1;

while (decimalNumber != 0)
{
binaryNumber += (decimalNumber % 2) * i;
decimalNumber /= 2;
i *= 10;
}

return binaryNumber;
}