实验5

#include <stdio.h>
const int N=5;
int binarySearch(int x[], int n, int item);
int main() 
{
    int a[N]={1,3,9,16,21};
    int i,index, key;
    printf("数组a中的数据:\n");
    for(i=0;i<N;i++)
        printf("%d ",a[i]);
    printf("\n");
    printf("输入待查找的数据项: ");
    scanf("%d", &key);
    index=binarySearch(a,5,key);
    if(index>=0)
        printf("%d在数组中，下标为%d\n", key, index);
    else
        printf("%d不在数组中\n", key);
    return 0;
}
int binarySearch(int x[], int n, int item) 
{
    int low, high, mid;
    low = 0;
    high = n-1;
    while(low <= high) 
	{
        mid = (low+high)/2;
        if (item == x[mid])
            return mid;
        else if(item < x[mid])
            high = mid - 1;
        else
            low = mid + 1;
    }
    return -1;
}

int binarySearch(int *x, int n, int item);
int main() 
{
    int a[N]={1,3,9,16,21};
    int i,index, key;
    printf("数组a中的数据:\n");
    for(i=0;i<N;i++)
    printf("%d ",a[i]);
    printf("\n");
    printf("输入待查找的数据项: ");
    scanf("%d", &key);
    index=binarySearch(a,5,key);
    if(index>=0)
        printf("%d在数组中，下标为%d\n", key, index);
    else
        printf("%d不在数组中\n", key);
    return 0;
}

int binarySearch(int *x, int n, int item) 
{
    int low, high, mid;
    low = 0;
    high = n-1;
    while(low <= high) 
	{
        mid = (low+high)/2;
        if (item == *(x+mid))
            return mid;
        else if(item < *(x+mid))
            high = mid - 1;
        else
            low = mid + 1;
    }
    return -1;
}

#include <stdio.h>
const int N=5;
void selectSort(int [], int); 
void input(int [], int);
void output(int [], int);
int main() 
{
    int a[N];
    printf("输入%d个整数\n", N);
    input(a, N);
    printf("排序前的数据:\n");
    output(a,N);
    selectSort(a,N); 
    printf("排序后的数据:\n");
    output(a, N);
    return 0;
}

void input(int a[], int n) 
{
    int i;
    for(i=0; i<n; i++)
    scanf("%d", &a[i]);
}

void output(int a[], int n) 
{
    int i;
    for(i=0; i<n; i++)
    printf("%d ", a[i]);
    printf("\n");
}

void selectSort(int a[], int n) 
{
    int i, j, k, temp;
    for(i=0; i<n-1; i++) 
	{
        k = i; 
        for(j=i+1; j<n; j++)
            if (a[j] < a[k])
                k = j; 
        if(k != i) 
 		{ 
            temp = a[i];
            a[i] = a[k];
            a[k] = temp;
        }
    }
}

#include <stdio.h>
#include <string.h>
void selectSort(char str[][20], int n );
int main() 
{
    char name[][20] = {"John", "Alex", "Joseph", "Candy", "Geoge"};
    int i;
    printf("输出初始名单:\n");
    for(i=0; i<5; i++)
    printf("%s\n", name[i]);
    selectSort(name, 5); 
    printf("按字典序输出名单:\n");
    for(i=0; i<5; i++)
        printf("%s\n", name[i]);
    return 0;
}

void selectSort(char str[][20], int n) 
{
	int i, j, k;
	char temp[20];
    for(i=0; i<n-1; i++) 
	{
        k = i; 
        for(j=i+1; j<n; j++)
        if(strcmp(str[j],str[k])<0)
                k = j; 
        if(k!=i) 
 		{ 
            strcpy(temp,str[i]);
            strcpy(str[i],str[k]);
            strcpy(str[k],temp);
        }
    }
}

#include <stdio.h>
void delPrefixStar(char []); 
int main() 
{
	char string[80];
    printf("输入一个字符串:\n");
    gets(string);
    printf("\n删除前导*之前的字符串:\n");
    puts(string);
    delPrefixStar(string); 
    printf("\n删除前导*之后的字符串:\n");
    puts(string);
    return 0;
}

void delPrefixStar(char s[]) 
{
    char *target, *source;
    source = s;
    while(*source == ‘*‘)
    source++;
    target = s;
    while( *target++ = *source++);
}

#include <stdio.h>
void delStarButPrefix(char []); 
int main() 
{
    char string[80];
    printf("输入一个字符串:\n");
    gets(string);
    printf("\n删除<中间和末尾的*>之前的字符串:\n");
    puts(string);
    delStarButPrefix(string);
    printf("\n除<中间和末尾的*>之后的字符串:\n");
    puts(string);
    return 0;
}

void delStarButPrefix(char s[]) 
{
    int i=0;
    char *p = s;
    while(*p && *p == ‘*‘) 
	{
        p++;
        i++;
    }
    while(*p) 
	{
        if(*p != ‘*‘) 
		{
            s[i] = *p;
            i++;
        }
        p++;
    }
    s[i] = ‘\0‘; 
}

#include <stdio.h>
void delMiddleStar(char []); 
int main() 
{
    char string[80];
    printf("输入一个字符串:\n");
    gets(string);
    printf("\n删除<中间和的*>之前的字符串:\n");
    puts(string);
    delMiddleStar(string);
    printf("\n删除<中间的*>之后的字符串:\n");
    puts(string);
    return 0;
}

void delMiddleStar(char s[]) 
{
    int i=0;
    char *tail, *head, *p;
    tail = s;
    while(*tail)
    tail++;
    tail--;
    while(*tail == ‘*‘)
    tail--;
    head = s;
    while(*head == ‘*‘)
    head++;
    p = s;
    while(p<=head) 
	{ 
        s[i] = *p;
        p++;
        i++;
    }
    while(p<tail) 
	{
		if(*p != ‘*‘) 
		{
            s[i] = *p;
            i++;
        }
        p++;
    }
    while(*p) 
	{
        s[i] = *p;
        i++;
        p++;
    }
    s[i] = ‘\0‘;
}