任意进制到10进制的转换

#include <iostream>
#include <string.h>
#include <stdio.h>

using namespace std;

long  toTen(char a[], int bit)
{
    int length = strlen(a);
    int i, b=1,sum=0; //i要做数组a的下标，注意其起止范围
    for(i=length-1; i>=0; i-- )
    {
        if(a[i]>='A')
        {
            sum += (a[i]-'A'+10) *b;
            b *= bit;
        }
        else
        {
            sum += (a[i]-'0') *b;
            b *= bit;
        }
    }
    return sum;
}
int main()
{
    int aNum,a;
    char cNum[20];
    cin>>aNum;
    sprintf(cNum,"%d",aNum);
    a = toTen(cNum,5)；//这里是5进制转10进制的模板
    return 0;
}