ACM Ex.1001
<SUM problem>:
Calculate integer summary;
Input:
Theinput is consist with series of integers n, one integer per line.
Output:
Sumresults, followed by a blank line. Output on the same file with the input.
Example: sample input “1
100”
sample output “
5050”
Key points:
a). normal loog test.
Meet Bugs:
a). fgets(), can be used to get on line in a file.
b). sscanf, argument is (*string,”template”,&var).
c). fprintf(),printf(), used very common for format output.
C Code:
#include <stdio.h>
#include <stdlib.h>
void main(void)
{
FILE*fp=NULL;
charch[100];
intstart=0;
intstop=0;
int i=0;
intsum=0;
fp=fopen("test1","r+");
fgets(ch,100,fp);
sscanf(ch,"%d",&start);
printf("start=%d\n",start);
fgets(ch,100,fp);
sscanf(ch,"%d",&stop);
printf("stop=%d\n",stop);
for(i=start;i<=stop;i++)
{
sum+=i;
}
fprintf(fp,"\n%d",sum);
printf("sum=%d\n",sum);
fclose(fp);
}
