进制转换

蓝桥的一题进制转换http://blog.csdn.net/laichilizi/article/details/79381732

#include<bits/stdc++.h>
using namespace std;
void Arbitrary_change(int n,int m){
    char s[100];
    int i;
    for(i=0;n>0;i++)
    {
        if(n%m<10)
            s[i] = n%m+'0';
        else
            s[i] = n%m-10+'A';
        n/=m; 
    }
    if(m == 8)
    {
        printf("Octal: "); 
        int temp = i;
        while(temp++<4)
            printf("0");
    }
    else if(m == 16)
    {
        printf("Hex: 0x");
        int temp = i;
        while(temp++<3)
            printf("0");
    }
    for(n=i;n>0;n--)
        printf("%c",s[n-1]);
    printf("\n");
}
 
int Ten_change(int n,string str)
{
    int ans = 0, sum = 1;
    for(int i = str.length(); i > 0; i--)
    {
        if(str[i-1] >='A') ans = ans + (str[i - 1] - 'A'+10) * sum;
        else ans = ans + (str[i - 1] - '0') * sum;
        //cout<<ans<<endl;
        sum *= n;
    }
    return ans;
    //printf("%d\n", ans);
}
 
int main()
{
    string str;
    cin>>str;
    int ans2 = Ten_change(16,str);
    Arbitrary_change(ans2,16);
    cout<<"Decimal: "<<ans2<<endl;
    Arbitrary_change(ans2,8);    
    return 0;