HDU 5055Bob and math problem(构造)

来源：互联网发布：windws10固态硬盘优化编辑：程序博客网时间：2024/05/01 20:24

无法输出的情况稍微难处理

其他的只要贪心构造一下就好了

#include<iostream>#include<cstdio>#include<set>#include<string>#include<string.h>#include<cstring>#include<vector>#include<map>#include<queue>#include<stack>#include<cctype>#include<algorithm>#include<sstream>#include<utility>#include<cmath>#include<functional>#define mt(a) memset(a,0,sizeof (a))#define fl(a,b,c) fill(a,b,c)#define SWAP(a,b,t) (t=a,a=b,b=t)#define inf 1000000000+7using namespace std;typedef long long ll;int main(){int n;while (cin >> n){int a[10] = { 0 };int odd = 0;for (int i = 0; i < n; i++){int x;cin >> x;a[x]++;if (x & 1)odd++;}if (odd == 0){ printf("-1\n"); continue; }if (n - odd - a[0] == 0 && odd == 1&&a[0]!=0){ printf("-1\n"); continue; }char  ans[130] = { 0 };for (int i = 0; i < 10; i++){if (a[i] && (i & 1)){ ans[n - 1] = (char)(i + '0'); a[i]--; break; }}for (int i = 0; i <n-1; i++){for (int j = 9; j >=0; j--){if (a[j]>0){ans[i] = (char)(j + '0');a[j]--;break;}}}printf("%s\n", ans);}return 0;}

0 0