题解 | 多项式输出

import sys

n, a, s = int(sys.stdin.readline()), list(map(int, sys.stdin.readline().strip().split())), ""
for i in range(n + 1):
    if a[i] == 0:
        continue
    if i == 0:
        if a[i] < 0:
            s += "-"
    else:
        s = s + "+" if a[i] > 0 else s + "-"
    if abs(a[i]) != 1 or n - i == 0:
        s += str(abs(a[i]))
    if n - i > 0:
        s += "x"
        if n - i > 1:
            s += f"^{n-i}"
print(s)