ch3-ArgsToInts (Print command-line args as ints in C/C++)

Chapter_3     Exercise_3-21     CommandLineArgs

Exercise_3-22

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ArgsToInts     TCP1, p. 202  (argstoints.c,  ArgsToInts.cpp)

argstoints.c         download

#include <stdio.h> // for printf()
#include <stdlib.h> // for atoi()

int main(int argc, char* argv[])
{
int i;

for(i = 1; i < argc; i++) // ignore argv[0], program name
{printf("%d\n", atoi(argv[i]));}

return 0;
}
/*
gcc argstoints.c -o argstoints
./argstoints // no args, prints nothing

./argstoints 10 010 0x10 // ignores octal and hex formats
10
10
0

./argstoints a b c // ignores ASCII
0
0
0

./argstoints .012 1.25 23.4E10 1.9 -0.9 // ignores fractional part
0
1
23
1
0

./argstoints 2147483647 -2147483648
2147483647 // INT_MAX // limits.h
-2147483648 // INT_MIN

./argstoints 2147483648 -2147483649 // 1 past limits
-2147483648 // INT_MIN (overflow, modulo 2 arithmetic)
2147483647 // INT_MAX (underflow)

./argstoints 2147483649 -2147483650 // 2 past limits
-2147483647 // INT_MIN + 1
2147483646 // INT_MAX - 1

./argstoints 12345678901234567890 -12345678901234567890
-1 // overflow, too big to handle
0 // underflow (20 digits)
*/

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ArgsToInts.cpp         download

#include <iostream>
#include <cstdlib> // for atoi()
using std::cout;
using std::endl;

int main(int argc, char* argv[])
{
for(int i = 1; i < argc; i++) // ignore argv[0], program name
{cout << atoi(argv[i]) << endl;}

return 0;
}
/*
g++ ArgsToInts.cpp -o ArgsToInts
./ArgsToInts // no args, prints nothing

./ArgsToInts 10 010 0x10 // ignores octal and hex formats
10
10
0

./ArgsToInts a b c // ignores ASCII
0
0
0

./ArgsToInts .012 1.25 23.4E10 1.9 -0.9 // ignores fractional part
0
1
23
1
0

./ArgsToInts 2147483647 -2147483648
2147483647 // INT_MAX // climits or limits.h
-2147483648 // INT_MIN

./ArgsToInts 2147483648 -2147483649 // 1 past limits
-2147483648 // INT_MIN (overflow, modulo 2 arithmetic)
2147483647 // INT_MAX (underflow)

./ArgsToInts 2147483649 -2147483650 // 2 past limits
-2147483647 // INT_MIN + 1
2147483646 // INT_MAX - 1

./ArgsToInts 12345678901234567890 -12345678901234567890
-1 // overflow, too big to handle
0 // underflow (20 digits)
*/

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Chapter_3     Exercise_3-21     CommandLineArgs

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Exercise_3-22