实验5

#include <stdio.h>
#define N 5

void output(int x[], int n);

int main()
{
    int x[N] = {9, 55, 30, 27, 22};
    int i;
    int k; // 用于记录最大元素的下标
    int t; // 用作交换两个数组元素的中间变量
    
    printf("original array:\n");
    output(x, N);
    
    k = 0;
    
    for(i=1; i<N; ++i)
        if(x[i] > x[k])
            k = i;

    if(k != N-1)
    {
        t = x[N-1];
        x[N-1] = x[k];
        x[k] = t;
    }

    printf("after swapped:\n");
    output(x, N);

    return 0;
}

void output(int x[], int n)
{
    int i;

    for(i=0; i<n; ++i)
        printf("%d ", x[i]);

    printf("\n");
}

 

 

 

 

#include <stdio.h>
#define N 5
void output(int x[], int n);
int main()
{
int x[N] = {9, 55, 30, 27, 22};
int i;
int t; // 用作交换两个数组元素的中间变量
printf("original array:\n");
output(x, N);
for(i=0; i<N-1; ++i)
if(x[i] > x[i+1])
{
t = x[i];
x[i] = x[i+1];
x[i+1] = t;
}
printf("after swapped:\n");
output(x, N);
return 0;
}
void output(int x[], int n)
{
int i;
for(i=0; i<n; ++i)
printf("%d ", x[i]);
printf("\n");
}

1交换1次

2交换3次

#include <stdio.h>
#define N 5

int binarySearch(int x[], int n, int item); // 函数声明

int main()
{
int a[N] = {2, 7, 19, 45, 66};
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,N,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>
#include<string.h>
#define N 5

void selectSort(char str[][20], int n);

int main()
{
char name[][20] = {"Bob", "Bill", "Joseph", "Taylor", "George"};
int i;

printf("输出初始名单:\n");
for (i = 0; i < N; i++)
printf("%s\n", name[i]);

selectSort(name, N);

printf("按字典序输出名单:\n");
for (i = 0; i < N; 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[k],str[j])>0)
k=j;
}
if(k!=i)
{
strcpy(temp,str[i]);
strcpy(str[i],str[k]);
strcpy(str[k],temp);
}
}
}

 

 

#include <stdio.h>
int main(){
int n;
int *pn;
n=42;
pn=&n;
printf("&n=%#x,n=%d\n",&n,n);
printf("&pn=%#x,pn=%#x\n",&pn,pn);
printf("*pn=%d\n",*pn);

return 0;
}

 

 

#include <stdio.h>

#define N 5

int main()
{
int a[N] = {1, 9, 2, 0, 7};
int i;
int *p;

for(i=0; i<N; ++i)
printf("&a[%d] = %#x, a[%d] = %d\n", i, &a[i], i, a[i]);

printf("\n");

for(i=0; i<N; ++i)
printf("a+%d = %#x, *(a+%d) = %d\n", i, a+i, i, *(a+i));

printf("\n");

p = a;
for(i=0; i<N; ++i)
printf("p+%d = %#x, *(p+%d) = %d\n", i, p+i, i, *(p+i));

return 0;
}

 

 

 

 

posted @ 2021-12-20 20:30  syzyyds  阅读(26)  评论(0编辑  收藏  举报