我需要从123开始的结果,如下所示.我想从头开始打印而不用sort().
1 2 3
1 2 4
1 2 5
…..
3 5 6
4 5 6
但是,结果如下所示.
4 5 6
3 5 6
2 5 6
1 5 6
3 4 6
2 4 6
1 4 6
2 3 6
1 3 6
1 2 6
3 4 5
2 4 5
1 4 5
2 3 5
1 3 5
1 2 5
2 3 4
1 3 4
1 2 4
1 2 3
result = "";
var N = 6;
var M = 3;
var arr = new Array(M);
combi(N, M, arr, M);
alert(result);
function combi(n, r, arr, sz) {
var i = n + 1;
while (i-- > r) {
// choose the first element
arr[r - 1] = i;
if (r > 1) { // if still needs to choose
// recursive into smaller problem
combi(i - 1, r - 1, arr, sz);
} else {
// print out one solution
var j = -1;
while (++j < sz) {
result += arr[j] + " ";
}
result += "\n";
}
}
}
解决方法:
除了所有的反转之外,你可以从一个和iterat开始直到想要的值.
function combination(n, r) {
function iter(i, temp) {
if (temp.length === r) { // set complete
result.push(temp.join(' ')); // join values
return;
}
if (i + r > n + 1 + temp.length) { // exit early
return;
}
iter(i + 1, temp.concat(i)); // take the value
iter(i + 1, temp); // go without the value
}
var result = []; // result set
iter(1, []); // start with 1 and
return result; // empty array for collecting sets
}
console.log(combination(6, 3));
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