#include <iostream> #include <algorithm> #include <string> using namespace std; string num1, num2; int a1[10005], a2[10005], len1, len2; bool sgn; bool cmp(string a, string b){ if(a.size() != b.size()) { return a.size() < b.size(); } return a < b; } int main() { freopen("subtraction.in","r",stdin); freopen("subtraction.out","w",stdout); cin >> num1 >> num2; if(cmp(num1,num2)){ sgn = true; swap(num1,num2); } len1 = num1.size(); for (int i = 0; i < len1; i++) { a1[i] = num1[len1 - 1 - i] - '0'; } len2 = num2.size(); for (int i = 0; i < len2; i++) { a2[i] = num2[len2 - 1 - i] - '0'; } for (int i = 0; i < len1; i ++){ a1[i] -= a2[i]; } for (int i = 0; i < len1; i ++){ while(a1[i] < 0){ a1[i + 1] --; a1[i] += 10; } } while(len1 > 1 && a1[len1 - 1] == 0){ len1 --; } if(sgn){ cout << "-"; } for (int i = len1 - 1; i >= 0; i--) { cout << a1[i]; } cout << endl; return 0;