1 #include <bits/stdc++.h>
 2 using namespace std;
 3
 4 typedef long long LL;
 5 const int maxn = 1010;
 6 typedef struct Point {
 7     int x, y;
 8     Point() {}
 9     Point(int xx, int yy) : x(xx), y(yy) {}
10 }Point;
11 int n;
12 LL ans;
13 Point p[maxn];
14
15 bool cmp(Point a, Point b) {
16     if(a.x == b.x) return a.y < b.y;
17     return a.x < b.x;
18 }
19
20 bool bs(int x, int y) {
21     int ll = 0, rr = n, mm;
22     while(ll <= rr) {
23         mm = (ll + rr) >> 1;
24         if(p[mm].x == x && p[mm].y == y) return 1;
25         else if(cmp(p[mm], Point(x, y))) ll = mm + 1;
26         else rr = mm - 1;
27
28     }
29     return 0;
30 }
31
32 int main() {
33     // freopen("in", "r", stdin);
34     int x3, y3, x4, y4;
35     while(~scanf("%d", &n) && n) {
36         ans = 1000000LL * 1001000LL;
37         for(int i = 0; i < n; i++) {
38             scanf("%d%d", &p[i].x, &p[i].y);
39         }
40         sort(p, p+n, cmp);
41         for(int i = 0; i < n; i++) {
42             for(int j = i + 1; j < n; j++) {
43                 x3 = p[i].x; y3 = p[j].y;
44                 x4 = p[j].x; y4 = p[i].y;
45                 if(bs(x3, y3) && bs(x4, y4)) {
46                     int a = x3 - x4;
47                     int b = y3 - y4;
48                     if((LL)a * b == 0) continue;
49                     ans = min(ans, abs((LL)a*b));
50                 }
51             }
52         }
53         printf("%lld\n", ans == 1000000LL * 1001000LL ? -1 : ans);
54     }
55     return 0;
56 }

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3
 4 const int maxn = 10;
 5 int n;
 6 set<string> ret;
 7 set<string>::iterator it;
 8 int num[maxn];
 9 set<int> pos;
10
11 int main() {
12     // freopen("in", "r", stdin);
13     // freopen("out", "w", stdout);
14     for(int i = 1; i < maxn; i++) num[i] = i;
15     while(~scanf("%d", &n)) {
16         ret.clear();
17         do {
18             int nn = (1 << (n));
19             for(int i = 0; i < nn; i++) {
20                 pos.clear();
21                 int tmp = i;
22                 int cnt = 0;
23                 while(tmp) {
24                     if(tmp & 1) pos.insert(cnt+1);
25                     tmp >>= 1; cnt++;
26                 }
27                 string t = "";
28                 bool ex = 0;
29                 t += (num[1] + '0');
30                 int pre = num[1];
31                 for(int i = 2; i <= n; i++) {
32                     if(ex) break;
33                     if(pos.find(i) != pos.end()) {
34                         t += '-';
35                         pre = -1;
36                     }
37                     if(pre > num[i]) {
38                         ex = 1;
39                         break;
40                     }
41                     t += (num[i] + '0');
42                     pre = num[i];
43                 }
44                 if(!ex) ret.insert(t);
45             }
46             // for(int i = 1; i <= n; i++) printf("%d", num[i]);
47             // printf("\n");
48         }while(next_permutation(num+1, num+n+1));
49         // printf("%d\n", ret.size());
50         for(it = ret.begin(); it != ret.end(); it++) {
51             cout << *it << endl;
52         }
53     }
54     return 0;
55 }

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3
 4 typedef long long LL;
 5 const int maxn = 1010;
 6 const LL mod = 1000000007LL;
 7 LL f[maxn], a[maxn];
 8 LL S[maxn][maxn];
 9 int n;
10
11 LL exgcd(LL a, LL b, LL &x, LL &y) {
12     if(b == 0) {
13         x = 1;
14         y = 0;
15         return a;
16     }
17     else {
18         LL ret = exgcd(b, a%b, x, y);
19         LL tmp = x;
20         x = y;
21         y = tmp - a / b * y;
22         return ret;
23     }
24 }
25
26 LL inv(LL a) {
27     LL x, y;
28     exgcd(a, mod, x, y);
29     return (x % mod + mod) % mod;
30 }
31
32 LL C(LL n, LL m) {
33     return f[n] * inv(f[m]) % mod * inv(f[n-m]) % mod;
34 }
35
36 LL mul(LL x, LL n) {
37     LL ret = 1;
38     while(n) {
39         if(n & 1) ret = ret * x % mod;
40         n >>= 1;
41         x = x * x % mod;
42     }
43     return ret;
44 }
45
46 int main() {
47     // freopen("in", "r", stdin);
48     // freopen("out", "w", stdout);
49     memset(S, 0, sizeof(S));
50     S[0][0] = 1;
51     for(int p = 1; p < maxn; p++) {
52         for(int k = 0; k < maxn; k++) {
53             S[p][k] = (LL)k * S[p-1][k] % mod + S[p-1][k-1] % mod;
54         }
55     }
56     f[0] = 1;
57     for(int i = 1; i < maxn; i++) {
58         f[i] = f[i-1] * (LL)i % mod;
59     }
60     memset(a, 0, sizeof(a));
61     a[0] = 1; a[1] = 1;
62     for(int i = 2; i <= 1000; i++) {
63         for(int k = 1; k <= i; k++) {
64             a[i] = (a[i] + f[k] * S[i][k] % mod) % mod;
65         }
66     }
67     while(~scanf("%d", &n)) {
68         printf("%lld\n", a[n]);
69     }
70     return 0;
71 }