北邮计算机考研复试题的C语言解答精选

  #include <stdio.h> 
  #include <string.h> 
  #include <stdlib.h> 
    
  struct stack 
  { 
    int top; 
    int data[100]; 
  }; 
    
  void convert_to_binary(struct stack *s,unsigned long int d) 
  { 
    s->top = 0; 
    
    while (d) { 
      s->data[s->top ++] = d % 2; 
      d /= 2; 
    } 
    
    while (s->top) { 
      printf("%d",s->data[-- s->top]); 
    } 
    printf("n"); 
  } 
    
  int main() 
  { 
    int i,n; 
    unsigned long int d; 
    struct stack *s = (struct stack*)malloc(sizeof(struct stack)); 
    
    while (scanf("%d",&n) != EOF) { 
      for (i = 0; i < n; i ++) { 
        scanf("%ld",&d); 
        if (d != 0) { 
          convert_to_binary(s,d); 
        }else { 
          printf("0n"); 
        } 
      } 
    } 
    
    return 0; 
  } 

 #include <stdio.h> 
  #include <stdlib.h> 
  #include <string.h> 
    
  struct btree 
  { 
    struct btree *lchild,*rchild; 
    unsigned long int data; 
  }; 
    
  struct btree* create_btree(struct btree *t,unsigned long int d,unsigned long int parent); 
    
  int main() 
  { 
    int i,n; 
    unsigned long int d; 
    struct btree *t; 
    
    while (scanf("%d",&n) != EOF) { 
      t = NULL; 
      for (i = 0; i < n; i ++) { 
        scanf("%ld",&d); 
        t = create_btree(t,d,-1); 
      } 
    } 
    
    return 0; 
  } 
    
  struct btree* create_btree(struct btree *t,unsigned long int parent) 
  { 
    if (t == NULL) { 
      t = (struct btree *)malloc(sizeof(struct btree)); 
      t->data = d; 
      t->lchild = NULL; 
      t->rchild = NULL; 
      printf("%ldn",parent);     
    }else if(t->data > d) { 
      t->lchild = create_btree(t->lchild,t->data); 
    }else if(t->data < d) { 
      t->rchild = create_btree(t->rchild,t->data); 
    }else { 
      exit(EXIT_FAILURE); 
    } 
    
    return t; 
  } 

  #include <stdio.h> 
  #include <stdlib.h> 
  #include <string.h> 
    
  #define LEN 15 
    
  int a[LEN][LEN],b[LEN][LEN],c[LEN][LEN]; 
    
  void multiplay_matrix(); 
    
    
  int main() 
  { 
    int t,n,k,i,j,d; 
    
    scanf("%d",&t); 
    while (t --) { 
      // 接收矩阵 
      scanf("%d %d",&n,&k); 
      for (i = 0; i < n; i ++) { 
        for (j = 0; j < n; j ++) { 
          scanf("%d",&d); 
          a[i][j] = d; 
          b[i][j] = d; 
          c[i][j] = d; 
        } 
      } 
    
      // 矩阵的幂 
      if (k != 1) { 
        multiplay_matrix(k,n); 
      } 
    
      for (i = 0; i < n; i ++) { 
        for (j = 0; j < n; j ++) { 
          if (j == n - 1) { 
            printf("%dn",c[i][j]); 
          }else { 
            printf("%d ",c[i][j]); 
          } 
        } 
      } 
    } 
    
    return 0; 
  } 
    
  void multiplay_matrix(int k,int n) 
  { 
    int i,h,data; 
    k --; 
    while (k --) { 
      for (i = 0; i < n; i ++) { 
        for (j = 0; j < n; j ++) { 
          for (h = data = 0; h < n; h ++) { 
            data += b[i][h] * a[h][j]; 
          } 
          c[i][j] = data; 
        } 
      } 
      for (i = 0; i < n; i ++) { 
        for (j = 0; j < n; j ++) { 
          b[i][j] = c[i][j]; 
        } 
      } 
    } 
  } 

  #include <stdio.h> 
  #include <stdlib.h> 
  #include <string.h> 
    
  #define LEN 1000 
    
  int change_tint(char *str,int begin,int num) 
  { 
    int i; 
    char *temp = (char *)malloc(sizeof(char) * (num + 1)); 
    
    for(i = 0; i < num; i ++) { 
      temp[i] = str[begin + i]; 
    } 
    temp[i] = ''; 
    
    return strtol(temp,NULL,16); 
  } 
    
  void ip_field(char *str,int num) 
  { 
    int i,flag,ip; 
    for (i = 0,flag = 1; i < num; i += 2) { 
      ip = change_tint(str,begin + i,2); 
      printf("%d",ip); 
      if (flag <= 3) { 
        printf("."); 
        flag ++; 
      } 
    } 
    printf("n"); 
  } 
    
    
  int main() 
  { 
    int index,length,ihl; 
    char ipstr[LEN],temp[LEN]; 
    
    while (scanf("%dn",&n) != EOF) { 
      if (n != 0) { 
        for (index = 1; index <= n; index ++) { 
          memset(ipstr,sizeof(ipstr)); 
          memset(temp,sizeof(temp));  
          gets(temp); 
          // 去除空格 
          for (i = j = 0,length = strlen(temp); i < length; i ++) { 
            if (temp[i] != ' ') { 
              ipstr[j ++] = temp[i]; 
            } 
          } 
          ipstr[j] = ''; 
    
          // 当前测试数据的序号 
          printf("Case #%dn",index); 
    
          // 整个ip数据包的长度 
          length = change_tint(ipstr,4,4); 
          printf("Total length = %d bytesn",length); 
    
          // 源ip地址和目的ip地址 
          printf("Source = "); 
          ip_field(ipstr,24,8); 
          printf("Destination = "); 
          ip_field(ipstr,32,8); 
    
          // 源端口号和目的端口号 
          ihl = change_tint(ipstr,1,1) * 4 * 2; 
          printf("Source Port = %dn",change_tint(ipstr,ihl,4)); 
          printf("Destination Port = %dn",ihl + 4,4)); 
          printf("n"); 
        } 
      } 
    } 
    return 0; 
  }