水题 HDOJ 4727 The Number Off of FFF

 1 /*
 2     水题：判断前后的差值是否为1，b[i]记录差值，若没有找到，则是第一个出错
 3 */
 4 #include <cstdio>
 5 #include <iostream>
 6 #include <algorithm>
 7 #include <cstring>
 8 #include <string>
 9 #include <cmath>
10 using namespace std;
11 
12 const int MAXN = 1e5 + 10;
13 const int INF = 0x3f3f3f3f;
14 int a[MAXN];
15 int b[MAXN];
16 
17 int main(void)        //HDOJ 4727 The Number Off of FFF
18 {
19     //freopen ("L.in", "r", stdin);
20 
21     int t, cas = 0;
22     int n;
23     scanf ("%d", &t);
24     while (t--)
25     {
26         scanf ("%d", &n);
27 
28         a[0] = b[0] = 0;
29         for (int i=1; i<=n; ++i)
30         {
31             scanf ("%d", &a[i]);
32             b[i] = a[i] - a[i-1];
33         }
34 
35         int ans = -1;
36         for (int i=2; i<=n; ++i)
37         {
38             if (b[i] != 1)
39             {
40                 ans = i;    break;
41             }
42         }
43         if (ans == -1)    ans = 1;
44 
45         printf ("Case #%d: %d\n", ++cas, ans);
46     }
47 
48     return 0;
49 }
50 
51 /*
52 Case #1: 3
53 Case #2: 3
54 */