C++ 解法, 执行用时: 4ms, 内存消耗: 524K, 提交时间: 2021-08-12 14:51:48

#include<bits/stdc++.h>
using namespace std;
#define int long long
int n,a[123],flag;
bool judge(int &x,int &y)
{
	string sx=to_string(x);
	for(auto &c:sx)
	{
		char d=c;
		c='9';
		if(stoll(sx)>y)
		{
			x=stoll(sx);
			return 1;
		}
		c=d;
	}
	string sy=to_string(y);
	for(int i=0;sy[i];i++)
	{
		char c=sy[i];
		sy[i]=i||!sy[1]?'0':'1';
		if(x>stoll(sy))
		{
			y=stoll(sy);
			return 1;
		}
		sy[i]=c;
	}
	return 0;
}
signed main()
{
	cin>>n;
	for(int i=0;i<n;i++)
	{
		cin>>a[i];
		if(i&&!flag)
		flag|=judge(a[i-1],a[i]);
	}
	if(flag)
	for(int i=0;i<n;i++)
	cout<<a[i]<<" \n"[i==n-1];
	else
	cout<<"impossible";
}

Python3 解法, 执行用时: 53ms, 内存消耗: 7040K, 提交时间: 2021-08-03 15:11:40

n = int(input())
a = input().split()

for i in range(n-1):
    if len(a[i]) == len(a[i+1]):
        b1 = '9' + a[i][1:]
        b2 = '1' + a[i+1][1:] if len(a[i]) > 1 else '0'
        if int(b1) > int(a[i+1]):
            a[i] = b1
            print(' '.join(a))
            break
        if int(a[i]) > int(b2):
            a[i+1] = b2
            print(' '.join(a))
            break
else:
    print('impossible')