day_11_9 實現數組交換，排序

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//實現三個數的交換
#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
void swap(int *x, int *y)
{
    int t;
    if (*x < *y)
    {
        t = *x;
        *x = *y;
        *y = t;
    }
}
int main()
{
    int a, b, c,t = 0;
    printf("請輸入三個數，用空格隔開\n");
    scanf("%d %d %d",&a,&b,&c); 
        swap(&a, &b);
        swap(&a, &c);
        swap(&b,&c);
    printf("%d %d %d\n",a,b,c);
    system("pause");
    return 0;
}

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//求兩個數的最大公約數
#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int max_cd(int *x, int *y)
{
    while (*x % *y != 0)
    {
        if (*x > *y)
            *x = *x - *y;
        else *y = *y - *x;
    }
    return *y;
}
int max_cd1(int *x,int *y)
{
    int z = 0;
    int min = *x > *y ? *y : *x;
    while (z = *x % *y != 0)
    {
        *x = *y;
        *y = *y % z;
    }
    return *y;
}
int main()
{   
    int a, b;
    int c = 0;
    printf("Please enter teo numbers\n");
    scanf("%d %d",&a,&b);
    c = max_cd(&a, &b);
    printf("a和b的最大公約數是:%d \n",c);
    c = max_cd1(&a, &b);
    printf("a和b的最大公約數是:%d \n", c);
    system("pause");
    return 0; 
}

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//輸出十個數中最大的一個
#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
    int i = 0;
    int max = 0;
    int a[10] = {1,6,5,9,8,7,3,4,12,2};
    for(i = 0; i < 10; i ++ )
    {
    printf("%d ",a[i]);
    }
    max = a[0];
    for (i = 1; i < 10; i++)
        {
        if (a[i]>max)
            max = a[i];     
        }
    printf("\n最大的值是:%d \n",max);
    system("pause");
    return 0;
}

//不使用臨時變量的交換方法
#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
    int i = 0;
    int j = 0;
    printf("請輸入兩個整數，用空格隔開\n");
    scanf("%d %d", &i,&j);
    i = i^j;
    j = i^j;
    i = j^i;
    printf("%d %d\n",i,j);
    system("pause");
    return 0;
}

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//交換兩個數，創建臨時變量
#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
    int a = 0;
    int b = 0;
    int t = 0;
    printf("請輸入兩個數，用空格隔開\n");
    scanf("%d %d", &a,&b);
    t = a;
    a = b;
    b = t;
    printf("%d %d",a,b);
    system("pause");
    return 0;
}

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