AcWing 791. 高精度加法
题目描述
给定两个正整数（不含前导 0），计算它们的和。
输入格式
共两行，每行包含一个整数。
输出格式
共一行，包含所求的和。
数据范围
1≤整数长度≤100000
输入样例：
12
23
输出样例：
35
C++
#include <iostream>
#include <string>using namespace std;void reverse(string &s) {size_t n = s.length();for (int i = 0; i < n / 2; ++i) {swap(s[i], s[n - i - 1]);}
}string add(string &a, string &b) {reverse(a);reverse(b);size_t n = max(a.size(), b.size()), carry = 0;string result;for (size_t i = 0; i < n; ++i) {if (i < a.size()) carry += a[i] - '0';if (i < b.size()) carry += b[i] - '0';result.push_back(carry % 10 + '0');carry /= 10;}if (carry) result.push_back(carry + '0');reverse(result);return result;
}int main() {string a, b;cin >> a >> b;cout << add(a, b) << endl;return 0;
}
#include <iostream>
#include <string>
#include <algorithm> // std::reverseusing namespace std;// 实现大整数相加的函数
string add(string &a, string &b) {// 反转字符串，使得从最低位开始相加reverse(a.begin(), a.end());reverse(b.begin(), b.end());size_t n = max(a.size(), b.size()), carry = 0;string result;for (size_t i = 0; i < n; i++) {if (i < a.size()) carry += a[i] - '0';if (i < b.size()) carry += b[i] - '0';result.push_back(static_cast<char>(carry % 10 + '0'));carry /= 10;}// 处理最高位的进位if (carry) result.push_back(static_cast<char>(carry + '0'));// 将结果反转回正确的顺序reverse(result.begin(), result.end());return result;
}int main() {string a, b;cin >> a >> b;cout << add(a, b) << endl;return 0;
}
#include <iostream>
#include <vector>using namespace std;vector<int> add(vector<int> &A, vector<int> &B) {if (A.size() < B.size()) return add(B, A);vector<int> C;int t = 0;for (size_t i = 0; i < A.size(); i++) {t += A[i];if (i < B.size()) t += B[i];C.push_back(t % 10);t /= 10;}if (t) C.push_back(t);return C;
}int main() {string a, b;vector<int> A, B;cin >> a >> b;for (size_t i = a.size(); i > 0; i--) A.push_back(a[i - 1] - '0');for (size_t i = b.size(); i > 0; i--) B.push_back(b[i - 1] - '0');auto C = add(A, B);for (size_t i = C.size(); i > 0; i--) cout << C[i - 1];cout << endl;return 0;
}
#include <iostream>
#include <vector>using namespace std;vector<int> add(vector<int> &A, vector<int> &B)
{if (A.size() < B.size()) return add(B, A);vector<int> C;int t = 0;for (int i = 0; i < A.size(); i ++ ){t += A[i];if (i < B.size()) t += B[i];C.push_back(t % 10);t /= 10;}if (t) C.push_back(t);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');auto C = add(A, B);for (int i = C.size() - 1; i >= 0; i -- ) cout << C[i];cout << endl;return 0;
}
Go
package mainimport ("fmt""strings"
)func reverse(s string) string {r := []rune(s)l := len(r)for i := 0; i < l/2; i++ {r[i], r[l-i-1] = r[l-i-1], r[i]}return string(r)
}func max(i int, j int) int {if i > j {return i}return j
}func add(a, b string) string {a = reverse(a)b = reverse(b)n := max(len(a), len(b))var carry uint8 = 0var res strings.Builderfor i := 0; i < n; i++ {if i < len(a) {carry += a[i] - '0'}if i < len(b) {carry += b[i] - '0'}res.WriteByte(carry%10 + '0')carry /= 10}if carry > 0 {res.WriteByte(carry + '0')}return reverse(res.String())
}func main() {var a, b stringfmt.Scanln(&a)fmt.Scanln(&b)fmt.Println(add(a, b))
}
模板
// C = A + B, A >= 0, B >= 0
vector<int> add(vector<int> &A, vector<int> &B)
{if (A.size() < B.size()) return add(B, A);vector<int> C;int t = 0;for (int i = 0; i < A.size(); i ++ ){t += A[i];if (i < B.size()) t += B[i];C.push_back(t % 10);t /= 10;}if (t) C.push_back(t);return C;
}
)
