水仙花数、Sn求和、输出菱形星、验证花括号

1.“水仙花数”是指一个三位数，其各位数字的立方和确好等于该数本身，如；153＝1＋5＋3，则153是一个“水仙花数”
#include <stdio.h>
#include <math.h>
#include<stdlib.h>
int main()
{
	int i = 0;
	int count = 0;
	int tmp = 0;
	for (i = 100; i < 100000; i++)
	{
		double sum = 0;
		tmp = i;
		count = 0;
		while (tmp)
		{	
			tmp = tmp / 10;
			count++;
		}//判断几位数
		tmp = i;
		while (tmp)
		{
			sum = sum + pow((tmp % 10), count);
			tmp = tmp / 10;
		}//每位三次方求和
		if (sum == i)
		{
			printf("%d\t", i);
		}
	}
	system("pause");
	return 0;
}
2.求Sn=a+aa+aaa+aaaa+aaaaa的前5项之和，其中a是一个数字，例如：2+22+222+2222+22222
# include<stdio.h>
int main()
{
	int a = 0;
	int n = 0;
	int i = 0;
  int sum = 0;
  int tmp = 0;
  scanf_s("%d%d", &a, &n);
  for (i = 0; i < n; i++)
  { 
	  tmp = tmp * 10 + a;
	  sum = sum + tmp;
  }
  printf("sum=%d\n", sum);
	return 0;
}
3.输出菱形的星
# include<stdio.h>
int main()
{  
	int line = 0;
		int i = 0;
		scanf("%d", &line);
		for (i = 0; i < line; i++)
		{
			int j = 0;
			for (j = 0; j < line 
				- 1 - i; j++)
			{
				printf(" ");
			}
		 for (j = 0; j < 2 * i + 1; j++)
		 {
			printf("*");
		}
		printf("\n");
		}
		for (i = 0; i < line - 1; i++)
		{
			int j = 0;
			for (j = 0; j <= i; j++)
			{
				printf(" ");
			}
			for (j = 0; j < (line - 1 - i) * 2 - 1; j++)
			{
				printf("*");
			}
			printf("\n");
		}
	return 0;
}
4..编写一个程序，它从标准输入读取C源代码，并验证所有的花括号都正确的成对出现

# include<stdio.h>
int main()
 {
 	int ch = 0;
 	int count = 0;
 	while((ch=getchar())!=EOF)
 	{
 		if(ch == '{')
 			count++;
 		else if(ch == '}' && count==0)
 		{	
 			printf("不匹配\n");
 			return 0;
 		}
 		else if(ch == '}' && count>0)
 		{
 			count--;
 		}
 	}
 	if(count == 0)
 	{
 		printf("匹配\n");
 	}
 	else
 	{
 		printf("不匹配\n");
 	}
 	return 0;
 }