002_C/C++笔试题_简单算法程序

 1 #include <iostream>
 2 using namespace std;
 3 void bubblesort(int a[], int m);
 4 int main(void)
 5 {
 6     int i;
 7     int array[]={5,4,8,44,56,4,5,9};
 8     bubblesort(array,sizeof(array)/4);/*sizeof(array)/4，取长度，int类型是4字节*/
 9     /*打印已经排序的数组*/
10     for(i = 0; i < sizeof(array)/4; i++)
11         printf("array[%d] = %d \n",i,array[i]);
12     return 0;    
13 }
14 void bubblesort(int a[], int m)
15 {
16         int i,j,z;
17         int tmp;
18         for(i = 0; i < m; i++)  //外层循环控制循环次数
19         {
20             for(j = 0; j < m-1-i; j++)    //内层循环控制每次循环里比较的次数。
21             {
22                 if(a[j] > a[j+1])
23                 {
24                     tmp = a[j];
25                     a[j] = a[j+1];
26                     a[j+1] = tmp;
27                 }
28             }
29             /*打印未排序*/
30             for(z = 0; z < m-1-i;z++)
31                 printf(" %d \t",a[z]);
32             printf("\n");
33          }
34 }

 1 #include <iostream>
 2 using namespace std;
 3 void selectionsort(int a[],int m);
 4 int main(void)
 5 {
 6     int i;
 7     int array[]={5,4,8,44,56,4,5,9};
 8     selectionsort(array,sizeof(array)/4);/*sizeof(array)/4，取长度，int类型是4字节*/
 9     /*打印已经排序的数组*/
10     for(i = 0; i < sizeof(array)/4; i++)
11         printf("array[%d] = %d \n",i,array[i]);
12     return 0;    
13 }
14 void selectionsort(int a[],int m)
15     {
16         int i,j;
17         int k;
18         int z;
19         int tmp;
20 
21         for(i = 0; i < m-1; i++)//控制循环次数，n个数需要n-1次循环
22         {
23             k = i;
24             for(j = i+1; j < m ; j++)
25             {
26                 if(a[j] < a[k])
27                     k = j;
28             }
29             //i不等于k是就证明a[i]不是最小的，
30             //i等于k时证明a[i]就是本轮比较过程中最小的值
31             if(i != k)
32             {
33                 tmp = a[i];
34                 a[i] = a[k];
35                 a[k] = tmp;
36             }
37             /*打印未排序*/
38             for(z = i; z < m;z++)
39                 printf(" %d \t",a[z]);
40             printf("\n");
41         }
42     }

 1 #include <iostream>
 2 using namespace std;
 3 char* my_strcpy(char *strDest,char *strSrc);
 4 int main(void)
 5 {
 6     char arr1[20] = { 1 };
 7     char arr2[20] = "abcdefghij";
 8     char *ret=my_strcpy(arr1,arr2);
 9     printf("%s\n", ret);//打印复制之后的字符串
10     return 0;    
11 }
12 char* my_strcpy(char *strDest,char *strSrc)
13 {
14     if(strSrc == NULL)
15         return NULL;
16     if(strDest == strSrc)
17         return strDest;
18     char *temp = strDest;
19     while((*strDest++ = *strSrc++) != ‘\0‘);
20     return temp;
21 }

 1 #include <iostream>
 2 
 3 using namespace std;
 4 
 5 #define MAX 10
 6  
 7 int mystrcmp(const char *str1,const char *str2);
 8 int main(int argc,char *argv[])
 9 {
10         char value;
11         char str1[MAX],str2[MAX];
12  
13         printf("Please input str1 and str2 :\n");
14         gets(str1);     //gets 和 printf的区别，gets可接收含空格的字符串，而scanf遇TAB，空格，回车即结束
15         gets(str2);
16     
17         value = mystrcmp(str1,str2);
18         printf("value :%d\n",value);
19     
20         return 0;
21 }
22  
23 int mystrcmp(const char *str1,const char *str2)
24 {
25         char i = 0;
26         for(; i < MAX, *(str1+i) != ‘\0‘,*(str2+i) != ‘\0‘; i++)
27         {
28                 if(*(str1+i) == *(str2+i))
29                         continue;            //相等时继续比较下一位
30                 return (*(str1+i) > *(str2+i))?1:(-1);
31         }
32         return 0;
33 }
34         

 1 #include <iostream>
 2 using namespace std;
 3 char* MyStrcat(char *dst, const char *src);
 4 int main(void)
 5 {
 6     char str1[10] = "abc";
 7     char str2[] = "bcd";
 8     char* str3 = MyStrcat(str1, str2);
 9 
10     printf("str1=%s\n", str1);
11     printf("str2=%s\n", str2);
12     printf("str3=%s\n", str3);
13     return 0;
14 }
15 
16 char* MyStrcat(char *dst, const char *src)
17 {
18     char *temp = dst;
19     while (*temp != ‘\0‘)
20         temp++;
21     while ((*temp++ = *src++) != ‘\0‘);
22     return dst;
23 }

 1 #include <iostream>
 2 using namespace std;
 3 int my_strlen(const char *str);
 4 int main(void)
 5 {
 6     printf("长度为：%d\n",my_strlen("abcd"));
 7     return 0;
 8 }
 9 
10 int my_strlen(const char *str)
11 {
12     int count = 0;
13     while(*str++)
14         count++;
15     return count;
16 }