1 #include<cstdio> 2 #include<cstring> 3 #include<iostream> 4 #include<algorithm> 5 #include<deque> 6 #include<cstdlib> 7 using namespace std; 8 typedef long long INT; 9 const INT MOD = 1000000007; 10 const int maxn = 2000000+5;11 char str[maxn],temp[maxn];12 int get_num(INT s,INT t)13 {14     for(int i = 0;i < t;++i)15     {16         s = s >> 1;17         if(s == 0)18         return 0;19     }20     return s;21 }22 int main()23 {24     while(gets(temp))25     {26         if(temp[0] == ‘#‘)27         break;28         int len = strlen(temp),f = 0;29         for(int i = 0;i < len; ++i)30         if(temp[i] != ‘ ‘)31         str[f++] = temp[i];32         str[f] = NULL;33         len = f;34         deque<INT> que1;35         deque<char> que2;36         //预处理37         for(int i = 0;i < len-2;++i)38         if(str[i] == ‘>‘ && str[i+1] == ‘>‘ && str[i+2] != ‘>‘)39         str[i] = str[i+1] = ‘^‘;40         char ss[20];       //缓存数字41         for(int i = 0;i < len;++i)42         {43             if(str[i] == ‘S‘  || str[i] == ‘s‘)44             {45                 i++;46                 que2.push_front(‘<‘);47             }48             if(str[i] == ‘>‘)49             {50                 INT tt = *que1.begin();51                 que1.pop_front();52                 que2.pop_front();    //计算完后把‘<‘弹出来53                 tt *= tt;54                 tt %= MOD;55                 if(*que2.begin() == ‘^‘)56                 {57                     INT tt2 = *que1.begin();58                     que1.pop_front();59                     que1.push_front(get_num(tt2,tt));60                     que2.pop_front();61                 }62                 else que1.push_front(tt);63             }64             if(str[i] == ‘^‘)65             {66                 i++;67                 que2.push_front(‘^‘);68             }69             if(str[i] >= ‘0‘ && str[i] <= ‘9‘)70             {71                 int ll = 0;72                 while(str[i] >= ‘0‘ && str[i] <= ‘9‘)73                 {74                     ss[ll++] = str[i];75                     i++;76                 }77                 i--;78                 ss[ll] = NULL;79                 int tt = atoi(ss);80                 if(*que2.begin() == ‘^‘)81                 {82                     int tt2 = *que1.begin();83                     que1.pop_front();84                     que2.pop_front();85                     que1.push_front(get_num(tt2,tt));  //get_num计算tt2 >> tt之后压回到栈中86                 }87                 else que1.push_front(tt);88             }89         }90         91         printf("%d\n",*que1.begin());92         que2.clear();93         que1.clear();94     }95     return 0;96 }