UVa 202 - Repeating Decimals

是道算循环节的题,一开始完全没有思路,看c++的书写到大整数类模拟手算进行,再加上看了 @xuziye0327 的一篇关于数据处理的博客,有的思路。从昨天上
上机课开始写,到现在,总算过了,错了好多次,细节处理总是不到位。PS:总是不长记性,上机课忘换行WA一次,最早做完的成第二了;接着做这道题,又少换行错好几次
。。

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#include<iostream>
#include<cstring>
#define maxn 10000
using namespace std;
int main()
{
int a,b,i,j,k,l,t,z,y;
int n[maxn],m[maxn];
while(cin>>a>>b)
{
t=0,z=0;
if(!a)
goto END;
m[0]=a%b;
n[0]=a/b;
if(!m[0])
{
cout<<a<<"/"<<b<<" = "<<n[0]<<".(0)"<<endl;
cout<<" 1 = number of digits in repeating cycle"<<endl;
cout<<endl;
continue;
}
for(i=1;i<maxn;i++)
{
n[i]=m[i-1]*10/b;
m[i]=m[i-1]*10%b;
if(m[i]==0)
{
z=1;
goto END;
}
for(j=i-1;j>0;j--)
{
if(m[i]==m[j]&&n[i]==n[j])
{
for(k=j;k<=i;k++)
if(n[k])
break;
if(k!=i)
goto END;
}
}
}
END:
if(a==0)
{
cout<<a<<"/"<<b<<" = "<<"0.(0)"<<endl;
cout<<" 1 = number of digits in repeating cycle"<<endl;
}
else
{
if(z)
{
cout<<a<<"/"<<b<<" = "<<n[0]<<".";
for(k=1;k<i+1;k++)
cout<<n[k];
cout<<"(0)"<<endl;
cout<<" 1 = number of digits in repeating cycle"<<endl;
}
else
{
cout<<a<<"/"<<b<<" = "<<n[0]<<".";
for(k=1;k<j;k++)
cout<<n[k];
y=k-1;
cout<<"(";
if(i-j<=50-y)
for(k=j;k<=i-1;k++)
cout<<n[k];
else
{
for(k=j;k<j+50-y;k++)
cout<<n[k];
cout<<"...";
}
cout<<")"<<endl;
cout<<" "<<i-j<<" = number of digits in repeating cycle"<<endl;
}
}
cout<<endl;
}
return 0;
}

本文迁移自我的 CSDN博客 ,格式可能有所偏差。