题解

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1010;
char str[N][N];
int len[N];
int main () {
	int cnt = 0,mx = -1;
	while(gets(str[cnt])) {
        len[cnt] = strlen(str[cnt]);
        mx = max(mx,len[cnt]);
        cnt++;
    }
    cnt--;
    string a(mx+2,'*');
    cout << a << endl;
    bool bt = false;
    for (int i = 0;i <= cnt;i++) {
    	cout << '*';
    	if (len[i] == 0) {
    		for (int j = 1;j <= mx;j++) cout << " ";
		} else {
    		int mid;
    		if ((mx - len[i]) % 2 == 1) {
	    		if (bt == false) {
	    			mid = (mx - len[i] - 1) / 2;
	    			for (int j = 1;j <= mid;j++)  cout << " ";
					cout << str[i];
					for (int j = 1;j <= mid+1;j++)  cout << " ";
					bt = true;
				} else {
					mid = (mx - len[i] + 1) / 2;
	    			for (int j = 1;j <= mid;j++) cout << " ";
					cout << str[i];
					for (int j = 1;j <= mid-1;j++) cout << " ";
					bt = false;
				}
			} else {
				mid = (mx - len[i]) / 2;
				for (int j = 1;j <= mid;j++) cout << " ";
				cout << str[i];
				for (int j = 1;j <= mid;j++) cout << " ";
			}
		}
		cout << "*\n";
	}
	cout << a << endl;
	return 0;
}