Little Boxes （C++大数加法）

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     */

#include 
using namespace std;
typedef long long ll;
#define inf 0x3f3f3f3f
const int maxn = 1010;

void asd(int x[], char y[])
{
    int len = strlen(y);
    for (int i = 0; i < len; i++)
    {
        x[i] = y[i] - '0';
    }
}

stack sa, sb, sc, sd, ans;

int main()
{
    ll T;
    int a[100], b[100], c[100], d[100];
    char aa[100], bb[100], cc[100], dd[100];
    int la, lb, lc, ld;
    cin >> T;
    while (T--)
    {
        scanf("%s %s %s %s", aa, bb, cc, dd);
        la = strlen(aa);
        lb = strlen(bb);
        lc = strlen(cc);
        ld = strlen(dd);

        asd(a, aa);
        asd(b, bb);
        asd(c, cc);
        asd(d, dd);

        for (int i = 0; i < la; i++)
            sa.push(a[i]);
        for (int i = 0; i < lb; i++)
            sb.push(b[i]);
        for (int i = 0; i < lc; i++)
            sc.push(c[i]);
        for (int i = 0; i < ld; i++)
            sd.push(d[i]);

        int pir = 0;

        for (;;)
        {
            if (sa.empty() && sb.empty() && sc.empty() && sd.empty())
                break;
            int aaa = 0, bbb = 0, ccc = 0, ddd = 0;
            if (!sa.empty())
            {
                aaa = sa.top();
                sa.pop();
            }
            if (!sb.empty())
            {
                bbb = sb.top();
                sb.pop();
            }
            if (!sc.empty())
            {
                ccc = sc.top();
                sc.pop();
            }
            if (!sd.empty())
            {
                ddd = sd.top();
                sd.pop();
            }
            int sum = aaa + bbb + ccc + ddd;
            ans.push((sum+pir)%10);
            pir = (sum+pir) / 10;
        }
        if(pir!=0)
            ans.push(pir);
        while (!ans.empty())
        {
            cout << ans.top();
            ans.pop();
        }
        cout << endl;
    }
    return 0;
}