题目描述
blablabla
样例
# include<iostream>
# include<vector>
using namespace std;
const int N = 1e6+10;
bool cmp(vector<int> &A,vector<int> &B){
if (A.size()!=B.size()) return A.size()>B.size();
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;
if (i<B.size()) t-=B[i];
C.push_back((t+10)%10);
if (t<0) t = 1;
else t=0;
}
while(C.size()>1&&C.back()==0) C.pop_back();
return C;
}
int main()
{
string a,b;
vector<int>A,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)){
auto C = sub(A,B);
for (int i = C.size()-1;i>=0;i--) cout<<C[i];
}
else {
auto C = sub(B,A);
cout<<"-";
for (int i = C.size()-1;i>=0;i--) cout<<C[i];
}
return 0;
}
算法1
(暴力枚举) $O(n^2)$
blablabla
时间复杂度
参考文献
C++ 代码
blablabla
算法2
(暴力枚举) $O(n^2)$
blablabla
时间复杂度
参考文献
C++ 代码
blablabla