I've done a quick benchmark on the existing answers which
- use only standard tools (sorry for stuff like
lua
or rocket
),
- are real one-liners,
- are capable of adding huge amounts of numbers (100 million), and
- are fast (I ignored the ones which took longer than a minute).
I always added the numbers of 1 to 100 million which was doable on my machine in less than a minute for several solutions.
Here are the results:
Python
:; seq 100000000 | python -c 'import sys; print sum(map(int, sys.stdin))'
5000000050000000
# 30s
:; seq 100000000 | python -c 'import sys; print sum(int(s) for s in sys.stdin)'
5000000050000000
# 38s
:; seq 100000000 | python3 -c 'import sys; print(sum(int(s) for s in sys.stdin))'
5000000050000000
# 27s
:; seq 100000000 | python3 -c 'import sys; print(sum(map(int, sys.stdin)))'
5000000050000000
# 22s
:; seq 100000000 | pypy -c 'import sys; print(sum(map(int, sys.stdin)))'
5000000050000000
# 11s
:; seq 100000000 | pypy -c 'import sys; print(sum(int(s) for s in sys.stdin))'
5000000050000000
# 11s
Awk
:; seq 100000000 | awk '{s+=$1} END {print s}'
5000000050000000
# 22s
Paste & Bc
This ran out of memory on my machine. It worked for half the size of the input (50 million numbers):
:; seq 50000000 | paste -s -d+ - | bc
1250000025000000
# 17s
:; seq 50000001 100000000 | paste -s -d+ - | bc
3750000025000000
# 18s
So I guess it would have taken ~35s for the 100 million numbers.
Perl
:; seq 100000000 | perl -lne '$x += $_; END { print $x; }'
5000000050000000
# 15s
:; seq 100000000 | perl -e 'map {$x += $_} <> and print $x'
5000000050000000
# 48s
Ruby
:; seq 100000000 | ruby -e "puts ARGF.map(&:to_i).inject(&:+)"
5000000050000000
# 30s
C
Just for comparison's sake I compiled the C version and tested this also, just to have an idea how much slower the tool-based solutions are.
#include <stdio.h>
int main(int argc, char** argv) {
long sum = 0;
long i = 0;
while(scanf("%ld", &i) == 1) {
sum = sum + i;
}
printf("%ld\n", sum);
return 0;
}
:; seq 100000000 | ./a.out
5000000050000000
# 8s
Conclusion
C is of course fastest with 8s, but the Pypy solution only adds a very little overhead of about 30% to 11s. But, to be fair, Pypy isn't exactly standard. Most people only have CPython installed which is significantly slower (22s), exactly as fast as the popular Awk solution.
The fastest solution based on standard tools is Perl (15s).