Programming

#include<cmath>
#include<cstdlib>
#include<iostream>
#include<fstream>
using namespace std;
int main ()
{
char filename [25];
ifstream  myfile;
cin.getline(filename,25);
myfile.open(filename);
if (!myfile.is_open())
{
exit (0);
}
char    number [25];
myfile >> number;
while (myfile.good ())
{

cout << number << " " << "\n";
myfile >> number ;
}
}

#include<cmath>
#include<cstdlib>
#include<iostream>
#include<fstream>
using namespace std;
int main ()
{
char filename [25];
ifstream  myfile;
cin.getline(filename,25);
myfile.open(filename);
if (!myfile.is_open())
{
exit (0);
}
int sum = 0, value;

while (myfile >> value)
       sum += value;
cout<<sum;
}

11 23 33 561

#include <stdio.h>

int main(void)
{
        int total=0, n;
        char buf[512];
        FILE *fp;

        fgets(buf, 512, stdin);
        for(n=0; buf[n]; n++) if((buf[n] == '\n') || (buf[n] == '\r')) buf[n]=0;

        if((fp=fopen(buf, "r")) == NULL) return(1);

        while(fgets(buf, 512, fp) != NULL) if(sscanf(buf, "%d", &n) == 1) total += n;

        fclose(fp);
        printf("Total is %d\n", total);
}