全WA，IDE测了数据是没问题的

#include <iostream>
#include <algorithm>
using namespace std;
int cal(int num)
{
    int wei = 0;
    if (num == 0)
        return 1;
    while (num >= 1 || num <= -1)
    {
        num /= 10;
        wei++;
    }
    return wei;
}
int main()
{
    int n, a, b, c;
    char ch,cht;
    cin >> n;
    cin >> ch;
    for (int i = 0; i < n; i++)
    {
        cin >> cht;
        int wei;
        if (cht >= '0' && cht <= '9')
        {
            char tnum[10005];
            int j;
            cin.get(tnum+1,10004);
            tnum[0] = cht;
            a = b = 0;
            for (j = 0; tnum[j] != ' '; j++)
                a = a * 10 + tnum[j] - '0';
            while (tnum[++j] != '\0')
            {
                b = b * 10 + tnum[j] - '0';
            }
        }
        else
        {
            cin >> a >> b;
            ch = cht;
        }
        switch (ch)
        {
        case 'a':
            c = a + b;
            wei = cal(a) + cal(b) + cal(c) + 2;
            printf("%d+%d=%d\n%d\n", a, b, c, wei);
            break;
        case 'b':
            c = a - b;
            wei = cal(a) + cal(b) + cal(c) + 2;
            if (c < 0)
                wei++;
            printf("%d-%d=%d\n%d\n", a, b, c, wei);
            break;
        case 'c':
            c = a * b;
            wei = cal(a) + cal(b) + cal(c) + 2;
            printf("%d*%d=%d\n%d\n", a, b, c, wei);
            break;
        }
    }
    return 0;
}

//