Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 | 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x | /**
* @license Apache-2.0
*
* Copyright (c) 2019 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// VARIABLES //
var TYPE_SORT_ORDER = {
'number': 0,
'string': 1,
'symbol': 2
};
// MAIN //
/**
* Returns the set difference between two similarly **sorted** lists.
*
* ## Notes
*
* - The contents of the provided arrays are assumed to be either numbers, strings, or symbols.
*
* - The lists are **expected** to be sorted not only, e.g., lexicographically, but also according to type in the **following** order: `numbers`, `strings`, and then `symbols`.
*
* ```text
* A = [ 1, 2, 3, '1', '2', '3', Symbol('1'), Symbol('2'), Symbol('3') ]
* B = [ 1, 2, '1', '3', Symbol('2'), Symbol('3') ]
* // => [ 3, '2', Symbol('1') ]
* ```
*
* @private
* @param {Array} A - first sorted list
* @param {Array} B - second sorted list
* @returns {Array} set difference
*
* @example
* var out = setdiff( [ 1, 2, 3 ], [ 2, 4, 5 ] );
* // returns [ 1, 3, 4, 5 ]
*
* @example
* var out = setdiff( [ 1 ], [ 2, 4, 5 ] );
* // returns [ 1, 2, 4, 5 ]
*
* @example
* var out = setdiff( [ 1, 2, 3 ], [ 2 ] );
* // returns [ 1, 3 ]
*
* @example
* var out = setdiff( [ 1, 2, 3 ], [] );
* // returns [ 1, 2, 3 ]
*
* @example
* var out = setdiff( [], [ 2, 4, 5 ] );
* // returns [ 2, 4, 5 ]
*
* @example
* var out = setdiff( [ 1, 2, 3 ], [ 1, 2, 3 ] );
* // returns []
*
* @example
* var out = setdiff( [], [] );
* // returns []
*
* @example
* var out = setdiff( [ 1 ], [ 1 ] );
* // returns []
*
* @example
* var out = setdiff( [ 1, 2, 2, 3, 3 ], [ 2, 4, 5, 5 ] );
* // returns [ 1, 2, 3, 3, 4, 5, 5 ]
*
* @example
* var out = setdiff( [ 1, 2, 3 ], [ 4, 5 ] );
* // returns [ 1, 2, 3, 4, 5 ]
*
* @example
* var out = setdiff( [ 1, 2 ], [ 3, 4, 5 ] );
* // returns [ 1, 2, 3, 4, 5 ]
*
* @example
* var out = setdiff( [ 1, 2, 3, 7 ], [ 0, 1, 2, 4, 5 ] );
* // returns [ 0, 3, 4, 5, 7 ]
*
* @example
* var out = setdiff( [ 1, 2, 3, 7, 9 ], [ -2, -1, 0, 1, 2, 4, 5 ] );
* // returns [ -2, -1, 0, 3, 4, 5, 7, 9 ]
*/
function setdiff( A, B ) {
var out;
var la;
var lb;
var ta;
var tb;
var a;
var b;
var i;
var j;
var k;
la = A.length;
lb = B.length;
if ( la === 0 ) {
return B.slice();
}
if ( lb === 0 ) {
return A.slice();
}
out = [];
i = 0;
j = 0;
while ( i < la && j < lb ) {
a = A[ i ];
b = B[ j ];
if ( a === b ) { // addresses numbers, strings, and symbols alike
i += 1;
j += 1;
continue;
}
ta = typeof a;
tb = typeof b;
if ( ta !== tb ) {
// Note: we assume we have found a "type" border!
ta = TYPE_SORT_ORDER[ ta ];
tb = TYPE_SORT_ORDER[ tb ];
if ( ta < tb ) {
out.push( a );
i += 1;
} else { // tb < ta
out.push( b );
j += 1;
}
}
// Note: the types for `a` and `b` are the *same*!
else if ( ta === 'symbol' ) {
// Note: symbols don't have a "natural" sort order, so we need to do things in a more computationally intensive way via linear scans...
while ( i < la ) {
for ( k = j+1; k < lb; k++ ) { // `j+1` because we already know the symbols are not equal
if ( a === B[ k ] ) {
break;
}
}
// If we searched through all the symbols in `B` and failed to find a match, we found a unique symbol...
if ( k === lb ) {
out.push( a );
} else {
// We can leverage the fact that symbols in `A` and `B` should be similarly sorted by recognizing that, if we found a match, this means that the symbols in `B` preceding the match should be unique...
for ( ; j < k; j++ ) {
out.push( B[ j ] );
}
}
i += 1;
}
} else if ( a < b ) {
out.push( a );
i += 1;
} else { // b < a
out.push( b );
j += 1;
}
}
if ( i < la ) {
for ( ; i < la; i++ ) {
out.push( A[ i ] );
}
}
if ( j < lb ) {
for ( ; j < lb; j++ ) {
out.push( B[ j ] );
}
}
return out;
}
// EXPORTS //
module.exports = setdiff;
|