//十进制转化为k进制
#include<stdio.h>
#include<string.h>
int main()
{
int n,r,i;
while(scanf("%d %d",&n,&r)!=EOF)
{
if(n<0)
{
printf("-");
n=-n;
}
if(n==0)
{
printf("0\n");
continue;
}
int c=0,a[100];
while(n!=0)
{
a[c++]=n%r;
n=n/r;
}
for(i=c-1;i>=0;i--)
{
if(a[i]>=10)
{
printf("%c",'A'+a[i]-10);
}
else
printf("%d",a[i]);
}
printf("\n");
}
return 0;
}
//m进制转化为十进制
#include<cstdio>
#include<iostream>
#include<cstdlib>
#include<cstring>
char a[10000];
using namespace std;
int main()
{
int n,m;
int f=0;
scanf("%s%d",a,&m);
for (int i=0;i<strlen(a);i++)
{
f*=m;
if (a[i]=='A'||a[i]=='B'||a[i]=='C'||a[i]=='D'||a[i]=='E'||a[i]=='F')
{
f=f+(a[i]-'A'+10);
}
else
{
f=f+(a[i]-'0');
}
}
printf ("%d",f);
return 0;
}
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