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;
}