数组和字符串简单练习

1.倒置一个int数组

int main(void)
{
int array[] = {23, 53, 53, 23, 231, 97, 234};
int i = 0;

int min = 0;
int max = sizeof(array) / sizeof(int) - 1;

while(min < max)
{
int tmp = array[min];
array[min] = array[max];
array[max] = tmp;

min ++;
max --;
}

for (i = 0; i < (sizeof(array)/sizeof(int)); i++)    {
printf("%d\n", array[i]);
}

return 0;
}

2.求一个数组中最大和第二大的数

int main(void)
{
int i = 0;
int array[7] = {23, 53, 53, 23, 231, 97, 234};

int max = 0;
int smax = 0;

if (array[1] > array[0])
{
max = array[1];
smax = array[0];
}
else
{
max = array[0];
smax = array[1];
}

for (i = 2; i < 7; i++)
{
if (max < array[i])
{
smax = max;
max = array[i];
}
else if (array[i] < max && array[i] > smax)
{
smax = array[i];
}
}

printf("smax = %d\n", smax);
printf("max = %d\n", max);

return 0;
}

3.中文汉字倒置

int main(void)
{
char a[] = "你好世界";
int length = 0;

while(a[length])
{
length++;
}
int min = 0;
int max = length - 1;

while(min < max)
{
char tmp = a[min];
a[min] = a[max - 1];
a[max - 1] = tmp;

tmp = a[min+1];
a[min+1] = a[max];
a[max] = tmp;

max -= 2;
min += 2;
}

printf("%s\n", a);

return 0;
}

4.求字符串中中文和英文字符的个数

int main(void)
{
char a[] = "你dsf好知了sdf世界d";
int length = 0;
int num = 0;
int c_num = 0;

while(a[length])
{
if (a[length] < 0)
{
num ++;
length += 2;
}
else
{
c_num++;
length++;
}
}

printf("num = %d, length = %d, c_num = %d\n", num ,length, c_num);

return 0;
}

5.冒泡排序

#include <stdio.h>

int main(void)
{
int i = 0 , j = 0;
int array[10];

for (i = 0; i < 10; i++)
{
scanf("%d", &array[i]);
}

for (i = 0; i < 10; i++)
{
for (j = 1; j < 10 - i; j++)
{
if (array[j-1] > array[j] )
{
int tmp = array[j-1];
array[j-1] = array[j];
array[j] = tmp;
}
}
}

printf("------------------------------\n");

for (i = 0; i < 10; i++)
{
printf("%d\n", array[i]);
}

return 0;
}

6.选择排序

#include <stdio.h>

int main(void)
{
int i = 0 , j = 0;
int array[10];

for (i = 0; i < 10; i++)
{
scanf("%d", &array[i]);
}

for (i = 0; i < 10; i++)
{
for (j = i + 1; j < 10; j++)
{
if (array[i] < array[j])
{
int tmp = array[i];
array[i] = array[j];
array[j] = tmp;

}
}
}

printf("------------------------------\n");

for (i = 0; i < 10; i++)
{
printf("%d\n", array[i]);
}

return 0;
}