高精度加法

const int N = 1e5 + 5; int a[N],b[N],c[N]; ///数组是按照低位在前的原则存,如123数组存的是321 void add(int *a,int *b) { memset(c,0,sizeof c); int i,j; for(j = N-1; j > 0; --j) if(a[j] || b[j]) break; for(i = 0; i <= j ; ++ i) { c[i] += a[i] + b[i]; if(c[i] >= 10) { c[i+1] += c[i]/10; c[i] %= 10; } } for(i = N-1; i > 0; -- i) if(c[i] != 0) break; for(; i >= 0; -- i) { printf("%d",c[i]); } printf("\n"); }

高精度减法

#include<bits/stdc++.h> using namespace std; const int N = 1e5 + 5; char s[N]; int a[N],b[N],c[N]; ///数组是按照低位在前的原则存,如123数组存的是321 bool check(int *a,int *b) //判断a是否大于b { for(int i = N-1; i >= 0; -- i) { if(a[i] > b[i]) return true; if(a[i] < b[i]) return false; } return true; } void sub(int *a,int *b) { memset(c,0,sizeof c); int i,j; for(j = N-1; j > 0; --j) if(a[j] || b[j]) break; for(i = 0; i <= j; ++ i) { c[i] += a[i] - b[i]; if(c[i] < 0) { c[i+1] -= 1; c[i] += 10; } } for(i = N-1; i > 0; -- i) if(c[i] != 0) break; for(; i >= 0; -- i) { printf("%d",c[i]); } printf("\n"); } int n; int main() { scanf("%s",s); n = strlen(s); for(int i = 0; i < n; ++ i) { a[i] = s[n-1-i] - '0'; } scanf("%s",s); n = strlen(s); for(int i = 0; i < n; ++ i) { b[i] = s[n-1-i] - '0'; } if(!check(a,b)) { swap(a,b); printf("-"); } sub(a,b); }

高精度乘法

#include<bits/stdc++.h> using namespace std; const int N = 1e5 + 5; char s[N]; vector<int>a; int b,n; void mul(vector<int>&a,int b) { int t = 0; for(int i = 0; i < a.size(); ++ i) { a[i] = a[i]*b + t; t = a[i]/10; a[i] %= 10; } while(t) { a.push_back(t%10); t/=10; } } void out(vector<int>a) { if(!a.back()) { printf("0\n"); return; } for(int i = a.size()-1; i >= 0; -- i) printf("%d",a[i]); printf("\n"); } int main() { scanf("%s",s); n = strlen(s); for(int i = 0; i < n; ++ i) { a.push_back(s[n-1-i] - '0'); } scanf("%d",&b); mul(a,b); out(a); }

高精度除法

#include<bits/stdc++.h> using namespace std; const int N = 1e5 + 5; char s[N]; vector<int>a; int b,n; void mul(vector<int>&a,int b) { int t = 0; for(int i = 0; i < a.size(); ++ i) { a[i] = a[i]*b + t; t = a[i]/10; a[i] %= 10; } while(t) { a.push_back(t%10); t/=10; } } int div(vector<int>&a,int b) { int t = 0, p; for(int i = a.size()-1; i >=0; --i ) { a[i] += t * 10; t = a[i]%b; a[i] = a[i]/b; } while(a.size() > 1 && !a.back()) a.pop_back(); return t; //返回余数 } void out(vector<int>a) { if(!a.back()) { printf("0\n"); return; } for(int i = a.size()-1; i >= 0; -- i) printf("%d",a[i]); printf("\n"); } int main() { scanf("%s",s); n = strlen(s); for(int i = 0; i < n; ++ i) { a.push_back(s[n-1-i] - '0'); } scanf("%d",&b); int t = div(a,b); out(a); printf("%d\n",t); }