算法学习之路 高精度算法
//高精度加法模板
#include<bits/stdc++.h>
using namespace std;
vector<int>add(vector<int> &A,vector<int>&B)
{
vector<int>C;
int t = 0;//进位;
for(int i = 0;i < A.size() || i < B.size() ;i++ )
{
if(i<A.size()) t+=A[i];
if(i<B.size()) t+=B[i];
C.push_back(t%10);
t = t/10;
}
if(t)
C.push_back(t);
return C;
}
int main()
{
string a;
string b;
vector<int>A;
vector<int>B;
cin>>a>>b;
for(int i=a.size()-1;i>=0;i--) A.push_back(a[i]-'0');
for(int i=b.size()-1;i>=0;i--) B.push_back(b[i]-'0');
auto C = add(A,B);
for(int i = C.size()-1;i >= 0;i--)
cout<<C[i];
return 0;
}
//高精度减法模板
#include<bits/stdc++.h>
using namespace std;
bool cmp(vector<int> &A,vector<int> &B)
{
if(A.size() != B.size())
return A.size() > B.size();
else
{
for (int i = A.size()-1; i >= 0; i--)
if(A[i] != B[i])
return A[i] > B[i];
}
return true;
}
vector<int> sub(vector<int> &A,vector<int> &B)
{
vector<int> C;
for(int i = 0,t = 0 ; i < A.size() ; i++)
{
t=A[i]-t;//减去借位数;
if(i < B.size())
t-=B[i];
C.push_back((t+10)%10);
if(t<0) t=1;
else
t=0;
}
//去除前导零;
while (C.size() > 1 && C.back()==0)
{
/* code */
C.pop_back();
}
return C;
}
int main()
{
string a;
string b;
vector<int>A;
vector<int>B;
cin>>a>>b;
for(int i=a.size()-1;i>=0;i--) A.push_back(a[i]-'0');
for(int i=b.size()-1;i>=0;i--) B.push_back(b[i]-'0');
if(cmp(A,B))
{
vector<int> C = sub(A,B);
for (int i = C.size()-1; i >= 0;i--)
{
/* code */
cout<<C[i];
}
}
else
{
vector<int> C = sub(B,A);
for (int i = C.size()-1; i >= 0; i--)
{
/* code */
cout<<C[i];
}
}
return 0;
}
//高精度乘法模板
#include<bits/stdc++.h>
using namespace std;
vector<int> mul(vector<int> &A,int b)
{
vector<int>C;
int t = 0;
for(int i = 0;i <= A.size()-1;i++ )
{
t += A[i]*b;
C.push_back(t%10);
t /= 10;
}
if(t) C.push_back(t);
return C;
}
int main()
{
string a;
int b;
vector<int>A;
cin>>a>>b;
for(int i=a.size()-1;i>=0;i--) A.push_back(a[i]-'0');
auto C = mul(A,b);
for(int i = C.size()-1 ;i >= 0 ;i--)
{
cout<<C[i];
}
return 0;
}
//高精度除法模板
#include<bits/stdc++.h>
using namespace std;
vector<int> div(vector<int> &A,int b,int &r)
{
vector<int>C;
r = 0;
for(int i = A.size()-1 ; i >= 0 ; i--)
{
r = (r * 10) + A[i];
C.push_back(r/b);
r %= b;
}
reverse(C.begin(),C.end());
while (C.size() > 1 && C.back() == 0)
{
/* code */
C.pop_back();
}
return C;
}
int main()
{
string a;
int b;
int r;//余数
vector<int>A;
cin>>a>>b;
for(int i=a.size()-1;i>=0;i--) A.push_back(a[i]-'0');
auto C = div(A,b,r);
for(int i = C.size()-1 ;i >= 0 ;i--)
{
cout<<C[i];
}
cout<<endl;
cout<<r;
return 0;
}