6 output reverse positive integer 1-4
Author: Turbo Time limit: 1S Section: branch structure
Problem Description:
Enter a positive integer not more than 4, and print out the required number on the respective bits in reverse order, for example, the original number 23, 32 to be output; The original number of 8000 and 0008 to be output; If the original number of 1 , 1 is output. Testing should be the following: a number of inputs, two, three, four positive integer; should also test the following exceptions: Input negative or 0, the number of input or more than four.
Input Description:
An integer that may be zero, or it may be negative.
Output Description:
input positive integer from 1 to 4, the reverse output of the number, if it is other integers, the output "error!". When the output of the line end of the line with no spaces.
Input Example:
8000
Sample output:
0008
Code:
#include <stdio.h>
int main()
{
int n, st[4] = {0};
int top = -1,i=0;
while (scanf("%d", &n) != EOF)
{
if (n<=0 || n>9999)
{
printf("error!");
}
else
{
while (n != 0)
{
top++;
st[top] = n % 10;
n /= 10;
}
while (i <= top)
{
printf("%d", st[i]);
i++;
}
}
printf("\n");
}
return 0;
}