参考答案：

#include<iostream>
using namespace std;
const int N = 1010;
int a[N], b[N], ans[N];
int main()
{
    int A, B;
    cin >> A >> B;
    int cnt = 0;
    while(A)
    {
        a[cnt ++] = A % 2;
        A /= 2;
    }
    int t = cnt - 1;
    cnt = 0;

    while(B)
    {
        b[cnt ++] = B % 2;
        B /= 2;
    }

    t = max(t, cnt - 1);

    for(int i = t; i >= 0; -- i ) ans[i] = a[i] + b[i];

    for(int i = t; i >= 0; -- i ) cout << ans[i];

    return 0;
}

参考答案 c++

简单版 ：

#include<iostream>
using namespace std;
const int N = 1010;
int a[N], b[N], ans[N];
int main()
{
    int A, B;
    cin >> A >> B;
    int cnt = 0;
    while(A)
    {
        a[cnt ++] = A % 2;
        A /= 2;
    }
    int t = cnt - 1;
    cnt = 0;

    while(B)
    {
        b[cnt ++] = B % 2;
        B /= 2;
    }

    t = max(t, cnt - 1);

    for(int i = t; i >= 0; -- i ) ans[i] = a[i] + b[i];

    for(int i = t; i >= 0; -- i ) cout << ans[i];

    return 0;
}

进阶版

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

vector<int> add(vector<int> &a , vector<int> &b)
{
    if (a.size() < b.size()) return add(b ,a);

    int t = 0;
    vector<int> c;

    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);

    reverse(c.begin() , c.end());

    return c;
}

int main()
{
    int n , m;
    cin >> n >> m;
    string s1 , s2;
    while (n)
    {
        int temp = n % 2;
        s1 += temp + '0';
        n /= 2;
    }

    while (m)
    {
        int temp = m % 2;
        s2 += temp + '0';
        m /= 2;
    }

    vector<int> a , b;
    for (int i = 0 ; i < s1.size() ; i ++ ) a.push_back(s1[i] - '0');
    for (int i = 0 ; i < s2.size() ; i ++ ) b.push_back(s2[i] - '0');

    vector<int> c = add(a , b);

    for (int i = 0 ; i < c.size() ; i ++ ) cout << c[i];
    return 0;
}