CSU 1421 Necklace

http://acm.csu.edu.cn/OnlineJudge/problem.php?id=1421
题意：给个项链，上面的元素有不同的颜色，分别进行rotate,flip,swap,paint操作，输出C，CS查询结果。
题解：模拟题……注意是一个环，边界的计数，totate、paint的边界都有坑……还有CS查询存在i==j的情况，要放在<的一类里……基本功不行，敲了3个多小时……
  1 #include <iostream>
  2 #include <cstring>
  3 #include <cstdio>
  4 #include <cstdlib>
  5 #include <cmath>
  6 #include <string>
  7 #include <vector>
  8 #include <list>
  9 #include <map>
 10 #include <queue>
 11 #include <stack>
 12 #include <bitset>
 13 #include <algorithm>
 14 #include <numeric>
 15 #include <functional>
 16 #include <set>
 17 #include <fstream>
 18 
 19 using namespace std;
 20 
 21 const int maxn=1010;
 22 int nec[maxn];
 23 int N;
 24 
 25 void rotate(int k)
 26 {
 27     int nec2[maxn];
 28     for (int i=1; i<=N; i++) {
 29         if (i+k>N) {
 30             nec2[(i+k)%N]=nec[i];
 31         }
 32         else nec2[i+k]=nec[i];
 33     }
 34     for (int i=1; i<=N; i++) {
 35         nec[i]=nec2[i];
 36     }
 37 }
 38 
 39 void flip()
 40 {
 41     /*for (int i=1,j=N-1; i<N/2; i++,j--) {
 42         swap(nec[i], nec[j]);
 43     }*/
 44     int co[maxn];
 45     co[1]=nec[1];
 46     for (int i=2; i<=N; i++) {
 47         co[N-i+2]=nec[i];
 48     }
 49     for (int i=1; i<=N; i++) {
 50         nec[i]=co[i];
 51     }
 52 }
 53 
 54 void myswap(int a,int b)
 55 {
 56     swap(nec[a], nec[b]);
 57 }
 58 
 59 void paint(int begin,int end,int colour)
 60 {
 61     for (int i=begin; i!=end ; i=(i+1)>N?1:i+1) {
 62         nec[i]=colour;
 63         //cout<<"n"<<i<<" "<<nec[i]<<endl;
 64     }
 65     nec[end]=colour;
 66 }
 67 
 68 void parts1()
 69 {
 70     int parts=0;
 71     int flag=0;
 72     for (int i=1; i<=N; i++) {
 73         if (nec[i]!=flag) {
 74             parts++;
 75             flag=nec[i];
 76         }
 77     }
 78     if (parts>1&&nec[1]==nec[N]) {
 79         parts--;
 80     }
 81     printf("%d
",parts);
 82 }
 83 
 84 void parts2(int begin,int end)
 85 {
 86     int parts2=0;
 87     int flag1=0;
 88     if (begin>end) {
 89         for (int i=begin; i<=N; i++) {
 90             if (nec[i]!=flag1) {
 91                // cout<<"c"<<i<<" "<<nec[i]<<endl;
 92                 flag1=nec[i];
 93                 parts2++;
 94             }
 95         }
 96         for (int i=1; i<=end; i++) {
 97             if (nec[i]!=flag1) {
 98                 //cout<<"c"<<i<<" "<<nec[i]<<endl;
 99                 flag1=nec[i];
100                 parts2++;
101             }
102         }
103     }
104     else if(begin<=end){
105         int flag2=0;
106         for (int i=begin; i<=end; i++) {
107             if (nec[i]!=flag2) {
108                 parts2++;
109                 flag2=nec[i];
110             }
111         }
112     }
113     printf("%d
",parts2);
114 }
115 
116 int main()
117 {
118    // freopen("/Users/apple/Desktop/csu 1421/csu 1421/in", "r", stdin);
119    // freopen("/Users/apple/Desktop/csu 1421/csu 1421/out", "w", stdout);
120     int C,M;
121     char o1[5]={'R'};
122     char o2[5]={'F'};
123     char o3[5]={'S'};
124     char o4[5]={'P'};
125     char q1[5]={'C'};
126     char q2[5]={'C','S'};
127     while ((scanf("%d%d",&N,&C))!=EOF) {
128         for (int i=1; i<=N; i++) {
129             scanf("%d",&nec[i]);
130         }
131         scanf("%d",&M);
132         char s[5];
133         for (int i=0; i<M; i++) {
134             cin>>s;
135             if (strcmp(s, o1)==0) {
136                 int k;
137                 cin>>k;
138                 rotate(k);
139             }
140             else if (strcmp(s, o2)==0) {
141                 flip();
142             }
143             else if (strcmp(s,o3)==0) {
144                 int i,j;
145                 cin>>i>>j;
146                 myswap(i, j);
147             }
148             else if (strcmp(s, o4)==0) {
149                 int i,j,x;
150                 cin>>i>>j>>x;
151                 paint(i, j,x);
152             }
153             else if (strcmp(s, q1)==0) {
154                 parts1();
155             }
156             else if (strcmp(s, q2)==0) {
157                 int i,j;
158                 cin>>i>>j;
159                 parts2(i,j);
160             }
161         }
162     }
163     return 0;
164 }