一百以内的偶数之和

一百之内偶数之和

#!/bin/bash
let sum=0
while [I=0;&I<100 ;I++]; do
H=$I%2==0
let $sum+=$H
done
~

#!/bin/bash
 sum=0
for I in {1..100};do
  if[$I%2==0]; then
 let sum+=$I
fi
done

#!/bin/bash (正确的）
 sum=0
 i=2
 while (($i <= 100 )) ; do
 sum=$((sum + i))
 ((i=i+2))
 done
 echo $sum;

#!/bin/bash
let sum=0
for I in {1..50 }
do
I=$I*2
sum=$[ $I+$sum ]
echo "the sum is $sum"