排序(qsort sort的使用)

 1 #include "stdio.h"
 2 #include "stdlib.h"
 3 #define N 1005
 4 int a[N];
 5 
 6 //此比较函数让数组从小到大排列
 7 int cmp(const void *a,const void *b){ return *(int *)a-*(int *)b; }
 8 
 9 int main()
10 {
11     int i,n;
12     scanf("%d",&n);
13     for(i=0; i<n; i++) scanf("%d",&a[i]);
14     qsort(a,n,sizeof(a[0]),cmp);
15     for(i=0; i<n; i++) printf("%d ",a[i]);
16     printf("\n");
17     return 0;
18 }

 1 #include "cstdio"
 2 #include "algorithm"
 3 using namespace std;
 4 #define N 1005
 5 int a[N];
 6 //sort函数不写比较函数的话，默认是从小到大排序的
 7 
 8 int main()
 9 {
10     int i,n;
11     scanf("%d",&n);
12     for(i=0; i<n; i++) scanf("%d",&a[i]);
13     sort(a,a+n); //将地址从a开始到a+n(不包括地址a+n对应元素)的所有数据进行排序
14     for(i=0; i<n; i++) printf("%d ",a[i]);
15     printf("\n");
16     return 0;
17 }

 1 #include "stdio.h"
 2 #include "string.h"
 3 #include "stdlib.h"
 4 #define N 1005
 5 char str[N];
 6 
 7 //此比较函数让数组从小到大排列
 8 int cmp(const void *a,const void *b){ return *(char *)a-*(char *)b; }
 9 
10 int main()
11 {
12     int len;
13     scanf("%s",str);
14     len = strlen(str);
15     qsort(str,len,sizeof(str[0]),cmp);
16     puts(str);
17     return 0;
18 }

 1 #include "cstdio"
 2 #include "cstring"
 3 #include "algorithm"
 4 using namespace std;
 5 #define N 1005
 6 char str[N];
 7 
 8 int main()
 9 {
10     int len;
11     scanf("%s",str);
12     len = strlen(str);
13     sort(str,str+len);  //默认也是按ascll码从小到大排序
14     puts(str);
15     return 0;
16 }

 1 #include "stdio.h"
 2 #include "string.h"
 3 #include "stdlib.h"
 4 #define N 1005
 5 double a[N];
 6 
 7 //此比较函数让数组从小到大排列
 8 int cmp(const void *a,const void *b)
 9 {
10     return *(double *)a > *(double *)b ? 1:-1;
11 }
12 
13 int main()
14 {
15     int i,n;
16     scanf("%d",&n);
17     for(i=0; i<n; i++) scanf("%lf",&a[i]);
18     qsort(a,n,sizeof(a[0]),cmp);
19     for(i=0; i<n; i++) printf("%.1lf ",a[i]);
20     printf("\n");
21     return 0;
22 }

 1 #include "cstdio"
 2 #include "cstring"
 3 #include "algorithm"
 4 using namespace std;
 5 #define N 1005
 6 double a[N];
 7 
 8 //从小到大排序
 9 bool cmp(double a,double b)
10 {
11     return a<b;
12 }
13 
14 int main()
15 {
16     int i,n;
17     scanf("%d",&n);
18     for(i=0; i<n; i++) scanf("%lf",&a[i]);
19     sort(a,a+n,cmp);
20     for(i=0; i<n; i++) printf("%.1lf ",a[i]);
21     printf("\n");
22     return 0;
23 }

 1 #include "stdio.h"
 2 #include "string.h"
 3 #include "stdlib.h"
 4 #define N 1005
 5 
 6 typedef struct
 7 {
 8     int x,y;
 9 }Point;
10 Point a[N];
11 //先按结构体中x从小到大排序，x相等的按y从大到小排序
12 int cmp(const void *a,const void *b)
13 {
14     Point *c = (Point *)a;
15     Point *d = (Point *)b;
16     if(c->x != d->x)
17         return c->x - d->x;
18     return d->y - c->y;
19 }
20 int main()
21 {
22     int i,n;
23     scanf("%d",&n);
24     for(i=0; i<n; i++) scanf("%d %d",&a[i].x,&a[i].y);
25     qsort(a,n,sizeof(a[0]),cmp);
26     for(i=0; i<n; i++) printf("%d %d\n",a[i].x,a[i].y);
27     return 0;
28 }

 1 #include "cstdio"
 2 #include "cstring"
 3 #include "algorithm"
 4 using namespace std;
 5 #define N 1005
 6 
 7 typedef struct
 8 {
 9     int x,y;
10 }Point;
11 Point a[N];
12 
13 //结构体中按x从小到大排序，x相等的按y从大到小排序
14 bool cmp(Point a,Point b)
15 {
16     if(a.x!=b.x)
17         return a.x < b.x;
18     return a.y > b.y;
19 }
20 
21 int main()
22 {
23     int i,n;
24     scanf("%d",&n);
25     for(i=0; i<n; i++) scanf("%d %d",&a[i].x,&a[i].y);
26     sort(a,a+n,cmp);
27     for(i=0; i<n; i++) printf("%d %d\n",a[i].x,a[i].y);
28     return 0;
29 }

 1 #include "stdio.h"
 2 #include "string.h"
 3 #include "stdlib.h"
 4 #define N 1005
 5 
 6 typedef struct
 7 {
 8     int data;
 9     char s[N];
10 }TT;
11 
12 TT str[N];
13 //对字符串数组按从小到大排序
14 int cmp(const void *a,const void *b)
15 {
16     TT *c = (TT *)a;
17     TT *d = (TT *)b;
18     return strcmp(c->s,d->s); //strcmp(s1,s2),若s1>s2,return 1;若s1<s2,return -1;
19 }
20 
21 int main()
22 {
23     int i,n;
24     scanf("%d",&n);
25     for(i=0; i<n; i++) scanf("%s",str[i].s);
26     qsort(str,n,sizeof(str[0]),cmp);
27     for(i=0; i<n; i++)
28         puts(str[i].s);
29     return 0;
30 }

 1 #include "cstdio"
 2 #include "cstring"
 3 #include "algorithm"
 4 using namespace std;
 5 #define N 1005
 6 
 7 typedef struct
 8 {
 9     int data;
10     char s[N];
11 }TT;
12 
13 TT str[N];
14 //对字符串数组按从小到大排序
15 bool cmp(TT a,TT b) //cmp只返回真或假
16 {
17     return strcmp(a.s,b.s)==-1; //strcmp(s1,s2),若s1>s2,return 1;若s1<s2,return -1;
18 }
19 
20 int main()
21 {
22     int i,n;
23     scanf("%d",&n);
24     for(i=0; i<n; i++) scanf("%s",str[i].s);
25     sort(str,str+n,cmp);
26     for(i=0; i<n; i++)
27         puts(str[i].s);
28     return 0;
29 }