水了好几下。
优化1：开始初始化的时候，如果左边那个也是最小值，那么此点就不用进队了。
优化2:如果队列里的位置，已经超过了后面位置的初始位置，那么后面这个位置也没用了。
1 /* 2 ID: cuizhe 3 LANG: C++ 4 TASK: hidden 5 */ 6 #include <cstdio> 7 #include <cstring> 8 #include <string> 9 #include <cmath> 10 #include <algorithm> 11 using namespace std; 12 int que1[200001],que2[200001]; 13 char str[300001]; 14 int main() 15 { 16 int i,len,minz,num,tnum,temp; 17 char ch; 18 freopen("hidden.in","r",stdin); 19 freopen("hidden.out","w",stdout); 20 scanf("%d",&len); 21 for(i = 0;i < len;) 22 { 23 scanf("%c",&ch); 24 if(ch != ' ') 25 str[i++] = ch; 26 } 27 for(i = len;i < 2*len;i ++) 28 { 29 str[i] = str[i-len]; 30 } 31 minz = 10000; 32 num = 0; 33 for(i = 0;i < len;i ++) 34 { 35 if(minz > str[i]-'a') 36 { 37 num = 0; 38 minz = str[i]-'a'; 39 que1[num++] = i; 40 } 41 else if(minz == str[i]-'a') 42 { 43 if(i != 0&&str[i-1]-'a' == minz) 44 continue;//优化1 45 que1[num++] = i; 46 } 47 } 48 for(temp = 0;;temp ++) 49 { 50 if(num == 1) break; 51 minz = 10000; 52 for(i = 0;i < num;i ++) 53 { 54 if(minz > str[que1[i]+1]-'a') 55 { 56 minz = str[que1[i]+1]-'a'; 57 tnum = 0; 58 que2[tnum++] = que1[i]+1; 59 } 60 else if(minz == str[que1[i]+1]-'a') 61 { 62 if(que2[tnum-1] >= que1[i]+1 -temp) 63 continue;//优化2 64 que2[tnum++] = que1[i]+1; 65 } 66 } 67 for(i = 0;i < tnum;i ++) 68 que1[i] = que2[i]; 69 num = tnum; 70 } 71 printf("%d ",que1[0]-temp); 72 return 0; 73 }