day_11_9 实现数组交换，排序

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//实现三个数的交换#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("请输入三个数，用空格隔开\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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//求两个数的最大公约数#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的最大公约数是:%d \n",c);    c = max_cd1(&a, &b);    printf("a和b的最大公约数是:%d \n", c);    system("pause");    return 0; }

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//输出十个数中最大的一个#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;}//不使用临时变量的交换方法#define _CRT_SECURE_NO_WARNINGS 1#include <stdio.h>int main(){    int i = 0;    int j = 0;    printf("请输入两个整数，用空格隔开\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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//交换两个数，创建临时变量#define _CRT_SECURE_NO_WARNINGS 1#include <stdio.h>int main(){    int a = 0;    int b = 0;    int t = 0;    printf("请输入两个数，用空格隔开\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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