题解 | #统计所有进程占用内存大小的和#

# 1
let sum=0
for i in $(awk '{print $6}' nowcoder.txt); do
    ((sum+=$i))
done
echo $sum

# 2
awk '{sum+=$6}END{print sum}' nowcoder.txt
# 3
awk 'BEGIN{sum=0}{sum+=$6}END{print sum}' nowcoder.txt
# 4
sum=0;
while read p
do
    arr=($p)
    ((sum+=arr[5]))
done <nowcoder.txt
echo $sum