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 ",*que1.begin()); 92 que2.clear(); 93 que1.clear(); 94 } 95 return 0; 96 }