进制转换

先看带代码：

代码有错， 大家看看

#include<iostream>#include<cstring>using namespace std;const int maxn = 1000;void swap(char a, char b){    char temp;    temp = a;    a = b;    b = temp;}void chg(char s[], char ans[], int r1, int r2){//先将其转换为10进制    int res = 0;    int len = strlen(s);    for(int i = 0 ; i < len ; i++)    {        res*= r1;        res+=(s[i]-'0');    }    int i = 0;    while(res)    {        ans[i] = res%r2 +'0';        res/=r2;        i++;    }    for(int i = 0 ; i < len/2; i++)    {        swap(ans[i], ans[len-1-i]);    }}int main(){    char s[maxn];    char ans[maxn];    int r1, r2;    while(true)    {        cin>>s>>r1>>r2;        chg(s, ans, r1, r2);        cout<<ans<<endl;    }    return 0;}