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need help with c program

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# 1  
Old 04-24-2009
need help with c program
Write a C program which reads the file “input.txt” and counts the occurrence frequency of each digit (0,
1, 2, ..., 9) and letter (A/a, B/b, ..., Z/z). Then, use fork() to duplicate a child process to write the most
frequent digit and letter at the end of the file “input.txt”. The parent process output the occurrence
frequency of each digit and letter to the terminal (using “printf”). You must invoke the function
“mostfrequent” (which is defined as follows) in your program (it can be used for calculating the most
frequent digit and letter)

here is what i had.
int mostfrequent(int * a, int length)/*length is the length of the array. The function returns the index of
the largest value of array a.*/
{
int index=0;
int max=a[0];
int i;
for(i=1;i<length;i++)
if (a[i]>max)
{
max = a[i];
index = i;
}
return index;
}
int main() {
char c;
int i, nwhite, nother;
int ndigit[10];
nwhite = nother = 0;
for (i=0; i<10; ++i)
ndigit[i] = 0;
while ((c = getchar()) != EOF)
if (c >= '0' && c <= '9')
++ndigit[c
‐'0'];
else if (c == ' ' || c == '\n' || c == '\t')
++nwhite;
else
++nother;
printf("digits = ");
for (i=0; i<10; ++i)
printf("%d ",ndigit[i]);
printf(", white space = %d, other = %d\n",nwhite, nother);
printf("The most frequent digit is '%c'\n",'0'+mostfrequent(ndigit,10));

}
# 2  
Old 04-26-2009
.....
# 3  
Old 04-26-2009
Please use CODE tags, that's too difficult to read that way...
Zykl0n-B
# 4  
Old 04-27-2009
Sounds like homework... this is simple code that does some of what you ask.
If you get stuck changing this code to meet your needs ask for more help. Show us what you've done first.
Code:
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>

int main(int argc, char **argv)
{
    int arr[255]={0};
    int cnt=0;
	FILE *in=fopen(argv[1], "r");
	int i=0;
	
	while( (i=fgetc(in))!=EOF)
		arr[i]++;
	fclose(in);
	for(i='0'; i<'z'; i++)
	{
	   	if(isalnum(i) )
			fprintf(stdout, "count %c: %d\n", i, arr[i]);
	}
	
	return 0;
}

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