下面是一段求解当 $\frac {-b - √Δ} {2a}$ 的值最大时的解，接下来该咋写啊，不会了qwq，题目传送门

void printf_solution_(int a, int b, int c) { //打印答案
    int delta = pow(b, 2) - 4 * a * c;
    int p, q;
    if(delta == 0) {
        p = -b;
        q = 2 * a;
        if(p % q == 0) {
            cout <<p / q <<endl;
            return;
        }
        else {
            int tmp = __gcd(p, q);
            p /= tmp;
            q /= tmp;
            if(q < 0 || p < 0) {
                cout <<"-" <<abs(p) <<"/" <<abs(q) <<endl;
                return;
            }
            else {
                cout <<p <<"/" <<q <<endl;
                return;
            }
        }
    }
    else {
     	int q1, q2, q3, r;
        <···>; //这里不废了qwq
    }
}