Sometimes you may encounter situations, when you wish to display all possible combinations of characters from given charset (e.g. some brute-force task). For example, print “a … zzz”, i.e. range is “a … z” and maximum length is 3. You can easily do this in bash (print recursively).
Simply adjust the script below to your needs and run it:
#!/bin/bash
[[ ! "${1}" =~ ^[0-9]+$ ]] && exit 1
charset=({a..z} {0..9})
permute() {
[[ "${1}" -eq 0 ]] && { echo -n "${2} "; return; }
for char in "${charset[@]}"; do
permute "$((${1}-1))" "${2}${char}"
done
}
for i in $(seq 1 ${1}); do
permute "${i}"
done
echo
exit 0Expected output:
[root@linux ~]# ./permute.sh 2
a b c d e f g h i j k l m n o p q r s t u v w x y z 0 1 2 3 4 5 6 7 8 9 aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az a0 a1 a2 a3 a4 a5 a6 a7 a8 a9 ba bb bc bd be bf bg bh bi bj bk bl bm bn bo bp bq br bs bt bu bv bw bx by bz b0 b1 b2 b3 b4 b5 b6 b7 b8 b9 ca cb cc cd ce cf cg ch ci cj ck cl cm cn co cp cq cr cs ct cu cv cw cx cy cz c0 c1 c2 c3 c4 c5 c6 c7 c8 c9 da db dc dd de df dg dh di dj dk dl dm dn do dp dq dr ds dt du dv dw dx dy dz d0 d1 d2 d3 d4 d5 d6 d7 d8 d9 ea eb ec ed ee ef eg eh ei ej ek el em en eo ep eq er es et eu ev ew ex ey ez e0 e1 e2 e3 e4 e5 e6 e7 e8 e9 fa fb fc fd fe ff fg fh fi fj fk fl fm fn fo fp fq fr fs ft fu fv fw fx fy fz f0 f1 f2 f3 f4 f5 f6 f7 f8 f9 ga gb gc gd ge gf gg gh gi gj gk gl gm gn go gp gq gr gs gt gu gv gw gx gy gz g0 g1 g2 g3 g4 g5 g6 g7 g8 g9 ha hb hc hd he hf hg hh hi hj hk hl hm hn ho hp hq hr hs ht hu hv hw hx hy hz h0 h1 h2 h3 h4 h5 h6 h7 h8 h9 ia ib ic id ie if ig ih ii ij ik il im in io ip iq ir is it iu iv iw ix iy iz i0 i1 i2 i3 i4 i5 i6 i7 i8 i9 ja jb jc jd je jf jg jh ji jj jk jl jm jn jo jp jq jr js jt ju jv jw jx jy jz j0 j1 j2 j3 j4 j5 j6 j7 j8 j9 ka kb kc kd ke kf kg kh ki kj kk kl km kn ko kp kq kr ks kt ku kv kw kx ky kz k0 k1 k2 k3 k4 k5 k6 k7 k8 k9 la lb lc ld le lf lg lh li lj lk ll lm ln lo lp lq lr ls lt lu lv lw lx ly lz l0 l1 l2 l3 l4 l5 l6 l7 l8 l9 ma mb mc md me mf mg mh mi mj mk ml mm mn mo mp mq mr ms mt mu mv mw mx my mz m0 m1 m2 m3 m4 m5 m6 m7 m8 m9 na nb nc nd ne nf ng nh ni nj nk nl nm nn no np nq nr ns nt nu nv nw nx ny nz n0 n1 n2 n3 n4 n5 n6 n7 n8 n9 oa ob oc od oe of og oh oi oj ok ol om on oo op oq or os ot ou ov ow ox oy oz o0 o1 o2 o3 o4 o5 o6 o7 o8 o9 pa pb pc pd pe pf pg ph pi pj pk pl pm pn po pp pq pr ps pt pu pv pw px py pz p0 p1 p2 p3 p4 p5 p6 p7 p8 p9 qa qb qc qd qe qf qg qh qi qj qk ql qm qn qo qp qq qr qs qt qu qv qw qx qy qz q0 q1 q2 q3 q4 q5 q6 q7 q8 q9 ra rb rc rd re rf rg rh ri rj rk rl rm rn ro rp rq rr rs rt ru rv rw rx ry rz r0 r1 r2 r3 r4 r5 r6 r7 r8 r9 sa sb sc sd se sf sg sh si sj sk sl sm sn so sp sq sr ss st su sv sw sx sy sz s0 s1 s2 s3 s4 s5 s6 s7 s8 s9 ta tb tc td te tf tg th ti tj tk tl tm tn to tp tq tr ts tt tu tv tw tx ty tz t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 ua ub uc ud ue uf ug uh ui uj uk ul um un uo up uq ur us ut uu uv uw ux uy uz u0 u1 u2 u3 u4 u5 u6 u7 u8 u9 va vb vc vd ve vf vg vh vi vj vk vl vm vn vo vp vq vr vs vt vu vv vw vx vy vz v0 v1 v2 v3 v4 v5 v6 v7 v8 v9 wa wb wc wd we wf wg wh wi wj wk wl wm wn wo wp wq wr ws wt wu wv ww wx wy wz w0 w1 w2 w3 w4 w5 w6 w7 w8 w9 xa xb xc xd xe xf xg xh xi xj xk xl xm xn xo xp xq xr xs xt xu xv xw xx xy xz x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 ya yb yc yd ye yf yg yh yi yj yk yl ym yn yo yp yq yr ys yt yu yv yw yx yy yz y0 y1 y2 y3 y4 y5 y6 y7 y8 y9 za zb zc zd ze zf zg zh zi zj zk zl zm zn zo zp zq zr zs zt zu zv zw zx zy zz z0 z1 z2 z3 z4 z5 z6 z7 z8 z9 0a 0b 0c 0d 0e 0f 0g 0h 0i 0j 0k 0l 0m 0n 0o 0p 0q 0r 0s 0t 0u 0v 0w 0x 0y 0z 00 01 02 03 04 05 06 07 08 09 1a 1b 1c 1d 1e 1f 1g 1h 1i 1j 1k 1l 1m 1n 1o 1p 1q 1r 1s 1t 1u 1v 1w 1x 1y 1z 10 11 12 13 14 15 16 17 18 19 2a 2b 2c 2d 2e 2f 2g 2h 2i 2j 2k 2l 2m 2n 2o 2p 2q 2r 2s 2t 2u 2v 2w 2x 2y 2z 20 21 22 23 24 25 26 27 28 29 3a 3b 3c 3d 3e 3f 3g 3h 3i 3j 3k 3l 3m 3n 3o 3p 3q 3r 3s 3t 3u 3v 3w 3x 3y 3z 30 31 32 33 34 35 36 37 38 39 4a 4b 4c 4d 4e 4f 4g 4h 4i 4j 4k 4l 4m 4n 4o 4p 4q 4r 4s 4t 4u 4v 4w 4x 4y 4z 40 41 42 43 44 45 46 47 48 49 5a 5b 5c 5d 5e 5f 5g 5h 5i 5j 5k 5l 5m 5n 5o 5p 5q 5r 5s 5t 5u 5v 5w 5x 5y 5z 50 51 52 53 54 55 56 57 58 59 6a 6b 6c 6d 6e 6f 6g 6h 6i 6j 6k 6l 6m 6n 6o 6p 6q 6r 6s 6t 6u 6v 6w 6x 6y 6z 60 61 62 63 64 65 66 67 68 69 7a 7b 7c 7d 7e 7f 7g 7h 7i 7j 7k 7l 7m 7n 7o 7p 7q 7r 7s 7t 7u 7v 7w 7x 7y 7z 70 71 72 73 74 75 76 77 78 79 8a 8b 8c 8d 8e 8f 8g 8h 8i 8j 8k 8l 8m 8n 8o 8p 8q 8r 8s 8t 8u 8v 8w 8x 8y 8z 80 81 82 83 84 85 86 87 88 89 9a 9b 9c 9d 9e 9f 9g 9h 9i 9j 9k 9l 9m 9n 9o 9p 9q 9r 9s 9t 9u 9v 9w 9x 9y 9z 90 91 92 93 94 95 96 97 98 99
[root@linux ~]#