求大佬帮调：

#include <bits/stdc++.h>
using namespace std;
string Add(string a, string b) {
	int lena = a.size(), lenb = b.size();
	int lenc = max(lena, lenb);
	int da[5000], db[5000], dc[5000];
//	memset(da, 0, sizeof(da)); 
//	memset(db, 0, sizeof(db));
//	memset(dc, 0, sizeof(dc));
	for (int i = 0; i < lena; ++i)
		da[i] = a[lena - 1 - i] - '0';
	for (int i = 0; i < lenb; ++i)
		db[i] = b[lenb - 1 - i] - '0';
	for (int i = 0; i < lenc; ++i) {
		dc[i] = da[i] + db[i];
		dc[i + 1] = dc[i] / 10;
		dc[i] %= 10;
	}
	if (dc[lenc]) lenc++;
	for (int i = lenc - 1; i >= 0; --i)
		cout << dc[i];
}
int main() {
	string s1, s2;
	cin >> s1 >> s2;
	cout << Add(s1, s2);
}