计算1累加到100

awk 'BEGIN{sum=0;i=1;while(i<=100){sum+=i;i++};print sum}'

for i in {1..100};do let sum+=1;done;echo $sum

seq -s+ 100|bc

[04:45:33 root@C8-3-55 ~]#n=100;sum=0;for i in $(seq $n);do let sum+=i;done;echo sum=$sum
sum=5050