“盛大游戏杯”第15届上海大学程序设计联赛夏季赛暨上海高校金马五校赛 D

 1 #include<math.h>
 2 #include<string.h>
 3 #include<stack>
 4 #include<set>
 5 #include<queue>
 6 #include<vector>
 7 #include<map>
 8 #include<iostream>
 9 #include<algorithm>
10 #define MAXN 1010000
11 #define LL long long
12 #define ll __int64
13 #define INF 0xfffffff
14 #define mem(x) memset(x,0,sizeof(x))
15 #define PI acos(-1)
16 #define eps 1e-8
17 #define LL long long
18 #define ULL unsigned long long
19 using namespace std;
20 LL modl(LL a, LL b, LL c)        //快速幂取余a^b%c
21 {
22     LL res, t;
23     res = 1 % c;
24     t = a % c;
25     while (b)
26     {
27         if (b & 1)
28         {
29             res = res * t % c;
30         }
31         t = t * t % c;
32         b >>= 1;
33     }
34     return res;
35 }
36 int main(){
37     LL n;
38     while(cin>>n){
39         cout<<modl(2,n,1000000007)-1<<endl;
40     }
41     return 0;
42 }