[Jobdu] 题目1377：缓变序列

 1 #include <cstdio>
 2 #include <cstdlib>
 3 #include <cstring>
 4  
 5 int N;
 6 int A[10001];
 7  
 8 int main() {
 9     int tmp;
10     while (scanf("%d", &N) != EOF) {
11         memset(A, 0, sizeof(A));
12         bool flag = false;;
13         int min = 10000, max = 0;
14         for (int i = 0; i < N; ++i) {
15             scanf("%d", &tmp);
16             ++A[tmp];
17             min = min > tmp ? tmp : min;
18             max = max > tmp ? max : tmp;
19         }
20         tmp = 0;
21         for (int i = min; i <= max; ++i) {
22             if (A[i] == 0) {
23                 flag = false;
24                 break;
25             }
26             tmp = A[i] - tmp;
27             if (tmp <= 0 && i != max) {
28                 flag = false;
29                 break;
30             } 
31             if (tmp ==0 && i == max) { flag = true;}
32         }
33         if (flag) {
34             printf("YES\n");
35         } else {
36             printf("NO\n");
37         }
38     }
39     return 0;
40 }
41  
42 /**************************************************************
43     Problem: 1377
44     User: hupo250
45     Language: C++
46     Result: Accepted
47     Time:30 ms
48     Memory:1060 kb
49 ****************************************************************/