模版题，线段树区间赋值，反转，看别人代码敲的；
1 #include<stdio.h> 2 #include<string.h> 3 #define MAXD 132000 4 #define N 131070 5 int tree[4 * MAXD], rev[4 * MAXD], to[4 * MAXD], a[MAXD]; 6 void build(int cur, int x, int y) 7 { 8 int mid = (x + y) >> 1, ls = cur << 1, rs = (cur << 1) | 1; 9 tree[cur] = rev[cur] = 0; 10 to[cur] = -1; 11 if(x == y) 12 return ; 13 build(ls, x, mid); 14 build(rs, mid + 1, y); 15 } 16 void pushdown(int cur) 17 { 18 int ls = cur << 1, rs = (cur << 1) | 1; 19 if(to[cur] != -1) 20 { 21 to[ls] = to[rs] = to[cur]; 22 rev[ls] = rev[rs] = 0; 23 tree[ls] = tree[rs] = to[cur]; 24 to[cur] = -1; 25 } 26 if(rev[cur]) 27 { 28 rev[ls] = (rev[ls] + 1) & 1, rev[rs] = (rev[rs] + 1) & 1; 29 tree[ls] ^= 1, tree[rs] ^= 1; 30 rev[cur] = 0; 31 } 32 } 33 void color(int cur, int x, int y, int s, int t, int c) 34 { 35 int mid = (x + y) >> 1, ls = cur << 1, rs = (cur << 1) | 1; 36 if(x >= s && y <= t) 37 { 38 tree[cur] = to[cur] = c; 39 rev[cur] = 0; 40 return ; 41 } 42 pushdown(cur); 43 if(mid >= s) 44 color(ls, x, mid, s, t, c); 45 if(mid + 1 <= t) 46 color(rs, mid + 1, y, s, t, c); 47 } 48 void Reverse(int cur, int x, int y, int s, int t) 49 { 50 int mid = (x + y) >> 1, ls = cur << 1, rs = (cur << 1) | 1; 51 if(x >= s && y <= t) 52 { 53 tree[cur] ^= 1; 54 rev[cur] = (rev[cur] + 1) & 1; 55 return ; 56 } 57 pushdown(cur); 58 if(mid >= s) 59 Reverse(ls, x, mid, s, t); 60 if(mid + 1 <= t) 61 Reverse(rs, mid + 1, y, s, t); 62 } 63 void dfs(int cur, int x, int y) 64 { 65 int mid = (x + y) >> 1, ls = cur << 1, rs = (cur << 1) | 1; 66 if(x == y) 67 { 68 a[x] = tree[cur]; 69 return ; 70 } 71 pushdown(cur); 72 dfs(ls, x, mid); 73 dfs(rs, mid + 1, y); 74 } 75 void printresult() 76 { 77 int i, x, y, flag = 0; 78 dfs(1, 0, N); 79 for(i = 0; i <= N; i ++) 80 { 81 if(a[i]) 82 { 83 if(flag) 84 printf(" "); 85 else 86 flag = 1; 87 if(i & 1) 88 printf("(%d,", i >> 1); 89 else 90 printf("[%d,", i >> 1); 91 for(; a[i + 1]; i ++); 92 if(i & 1) 93 printf("%d)", (i + 1) >> 1); 94 else 95 printf("%d]", i >> 1); 96 } 97 } 98 if(flag == 0) 99 printf("empty set\n"); 100 printf("\n"); 101 } 102 void solve() 103 { 104 int x, y; 105 char op[5], b[20]; 106 while(scanf("%s%s", op, b) == 2) 107 { 108 sscanf(b + 1, "%d,%d", &x, &y); 109 if(b[0] == '(') 110 x = (x << 1) | 1; 111 else 112 x <<= 1; 113 if(b[strlen(b) - 1] == ')') 114 y = (y << 1) - 1; 115 else 116 y <<= 1; 117 if(op[0] == 'U') 118 color(1, 0, N, x, y, 1); 119 else if(op[0] == 'D') 120 color(1, 0, N, x, y, 0); 121 else if(op[0] == 'S') 122 Reverse(1, 0, N, x, y); 123 else if(op[0] == 'C') 124 { 125 if(x > 0) 126 color(1, 0, N, 0, x - 1, 0); 127 if(y < N) 128 color(1, 0, N, y + 1, N, 0); 129 Reverse(1, 0, N, x, y); 130 } 131 else 132 { 133 if(x > 0) 134 color(1, 0, N, 0, x - 1, 0); 135 if(y < N) 136 color(1, 0, N, y + 1, N, 0); 137 } 138 } 139 printresult(); 140 } 141 int main() 142 { 143 build(1, 0, N); 144 solve(); 145 return 0; 146 }