作业。。

  1 A：
  2 #include <iostream>
  3 #include <cstdio>
  4 #include <cstring>
  5 #include <algorithm>
  6 using namespace std;
  7 
  8 const int maxn = 105;
  9 struct Node {
 10     int a, b;
 11     int val;
 12 }node[maxn * maxn];
 13 
 14 bool cmp(Node n1, Node n2) {
 15     return n1.val < n2.val;
 16 }
 17 
 18 int fa[maxn];
 19 void init(int x) {
 20     for(int i = 0; i <= x; i++) {
 21         fa[i] = i;
 22     }
 23 }
 24 
 25 int find(int x) {
 26     if(fa[x] == x) {
 27         return fa[x];
 28     }
 29     return fa[x] = find(fa[x]);
 30 }
 31 
 32 int sum;
 33 void unin(int x, int y, int z) {
 34     int fx = find(x), fy = find(y);
 35     if(fx != fy) {
 36         sum += z;
 37         fa[fx] = fy;
 38     }
 39 }
 40 
 41 int main() {
 42     int n, m;
 43     while(EOF != scanf("%d %d",&n, &m) ) {
 44         init(n);
 45         for(int i = 0; i < m; i++){
 46             scanf("%d %d %d",&node[i].a, &node[i].b, &node[i].val);
 47         }
 48         sort(node, node + m, cmp);
 49         sum = 0;
 50         for(int i = 0; i < m; i++) {
 51             unin(node[i].a, node[i].b, node[i].val);
 52         }
 53         printf("%d\n", sum);
 54     }
 55     return 0;
 56 }
 57 
 58 
 59 B:
 60 #include <iostream>
 61 #include <cstdio>
 62 #include <cstring>
 63 using namespace std;
 64 
 65 const int maxn = 105;
 66 int mat[maxn][maxn];
 67 
 68 int main() {
 69     int n, m;
 70     int u, v, w;
 71     while(EOF != scanf("%d %d",&n, &m) ) {
 72         memset(mat, 0x3f, sizeof(mat));
 73         for(int i = 1; i <= m; i++) {
 74             scanf("%d %d %d",&u, &v, &w);
 75             mat[u][v] = min(mat[u][v], w);
 76             mat[v][u] = mat[u][v];
 77         }
 78         for(int k = 1; k <= n; k++) {
 79             for(int i = 1; i <= n; i++) {
 80                 for(int j = 1; j <= n; j++) {
 81                     if(k == i || k == j) continue;
 82                     if(mat[i][j] > mat[i][k] + mat[k][j]) {
 83                         mat[i][j] = mat[i][k] + mat[k][j];
 84                     }
 85                 }
 86             }
 87         }
 88         printf("%d\n", mat[1][n]);
 89     }
 90     return 0;
 91 }
 92 
 93 
 94 C:
 95 #include <iostream>
 96 #include <cstdio>
 97 #include <cstring>
 98 using namespace std;
 99 
100 const int maxn = 1030;
101 int a[maxn];
102 int n;
103 
104 void pr(int x) {
105     if(x > n) return ;
106     printf("%d ", x);
107     pr(x << 1);
108     pr(x << 1 | 1);
109 }
110 int main() {
111     while(EOF != scanf("%d",&n) ) {
112         for(int i = 1; i <= n; i++) {
113             a[i] = i;
114         }
115         pr(1); puts("");
116     }
117     return 0;
118 }
119 
120 
121 D:
122 #include <iostream>
123 #include <cstdio>
124 #include <cstring>
125 using namespace std;
126 
127 const int maxn = 1030;
128 int a[maxn];
129 int n;
130 
131 void pr(int x) {
132     if(x > n) return ;
133     pr(x << 1);
134     printf("%d ", x);
135     pr(x << 1 | 1);
136 }
137 int main() {
138     while(EOF != scanf("%d",&n) ) {
139         for(int i = 1; i <= n; i++) {
140             a[i] = i;
141         }
142         pr(1); puts("");
143     }
144     return 0;
145 }
146 
147 
148 
149 E:
150 #include <iostream>
151 #include <cstdio>
152 #include <cstring>
153 using namespace std;
154 
155 const int maxn = 1030;
156 int a[maxn];
157 int n;
158 
159 void pr(int x) {
160     if(x > n) return ;
161     pr(x << 1);
162     pr(x << 1 | 1);
163     printf("%d ", x);
164 }
165 int main() {
166     while(EOF != scanf("%d",&n) ) {
167         for(int i = 1; i <= n; i++) {
168             a[i] = i;
169         }
170         pr(1); puts("");
171     }
172     return 0;
173 }