12_打印三角形

一.打印三角

1.图一

#!/bin/bash

# 1
# 22
# 333
# 4444
# 55555
# 666666
# 7777777
# 88888888
# 999999999

for i in $(seq 9); do
    for ((j = 1; j <= i; j++)); do
        echo -n "$i"
    done
    echo ""
done

2.第二个图

#!/bin/bash

# |_
# ||_
# |||_
# ||||_
# |||||_


for i in $(seq 5); do
    for ((j = 1; j <= i; j++)); do
        echo -n "|"
    done
    echo "_"
done

3.第三个图

#!/bin/bash

# *
# * *
# * * *
# * * * *
# * * * * *
# * * * * *
# * * * *
# * * *
# * *
# *

# 方法一
for ((i = 1; i <= 5; i++)); do
    for ((j = 1; j <= i; j++)); do
        echo -n " *"
    done
    echo ""
done
for ((i=5; i>=1; i--)); do
    for((j=1;j<=i;j++));do
        echo -n " *"
    done
    echo ""
done

# 方法二
for i in $(seq 10); do
    if [ $i -gt 6 ]; then
        for m in $(seq $((11 - i))); do
            echo -n "* "
        done

    elif [ $i -eq 6 ]; then
        for j in $(seq $((i - 1))); do
            echo -n "* "
        done

    else
        for j in $(seq $i); do
            echo -n "* "
        done
    fi
    echo
done