#include<iostream>
#include<string>
using namespace std;
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string BigIntegerMod(const string &str1,const string &str2) // str1%str2
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{
int i;
int len,len1,len2,index;
bool flag;
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len1=str1.length();
len2=str2.length();
len=len1-len2;
if(len<0) return str1;
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int *num1=new int[len1+2];
int *num2=new int[len2+2];
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memset(num1,0,sizeof(int)*(len1+2));
memset(num2,0,sizeof(int)*(len2+2));
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for(i=len1-1,index=0;i>=0;--i)
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{
num1[index++]=str1[i]-'0';
}
for(i=len2-1,index=0;i>=0;--i)
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{
num2[index++]=str2[i]-'0';
}
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while(true)
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{
for(i=len1-1;i>=0;i--)
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{
if(num1[i])
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{
len1=i+1;
break;
}
if(i==0) len1=0;
}
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len=len1-len2;
if(len<0) break;
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flag=false;
index=0;
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for(i=len1-1;i>=len;i--)
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{
if(num1[i]==num2[i-len]) continue;
else if(num1[i]<num2[i-len])
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{
flag=true;
break;
}
else break;
}
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if(flag) --len;
if(len<0) break;
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while(++index)
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{
flag=false;
for(i=len1-1;i>=len;i--)
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{
if(num1[i]==num2[i-len]) continue;
else if(num1[i]<num2[i-len])
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{
flag=true;
break;
}
else break;
}
if(flag)
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{
--index;
break;
}
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for(i=len;i<len1;i++)
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{
num1[i]-=num2[i-len];
if(num1[i]<0)
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{
num1[i]+=10;
--num1[i+1];
}
}
}
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if(index==0) break;
}
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string ans;
flag=false;
for(i=len1;i>=0;--i)
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{
if(flag||num1[i])
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{
flag=true;
ans+='0'+num1[i];
}
}
if(!flag) ans="0";
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delete [] num1;
delete [] num2;
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return ans;
}
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int main()
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{
string str,str1,str2;
while(cin>>str1>>str2)
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{
str=BigIntegerMod(str1,str2);
cout<<str<<endl;
}
return 0;
}
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posted on 2011-07-31 15:24
wuxu 阅读(505)
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