相当奇怪的是,我构建了一个搜索树并进行搜索。在搜索功能中,如果我动态分配内存并删除,内存限制将超过(我在OJ中解决问题)。但是,如果我只声明一个普通变量,就没有内存不足的问题。代码如下所示:(我递归搜索树(类似于2DTree))
void Search(int x1, int x2, int y1, int y2, node* n, int* st, long long* tem) {
int nx, ny, nx1, nx2, ny1, ny2;
nx = n->x; ny = n->y;
nx1 = n->x1; nx2 = n->x2;
ny1 = n->y1; ny2 = n->y2;
node* l = n->lc;
node* r = n->rc;
if (x1 > nx2 || x2<nx1 || y1>ny2 || y2 < ny1) {
*st = 0;
*tem = 0;
return;
}
else if (x1 <= nx1 && x2 >= nx2 && y1 <= ny1 && y2 >= ny2) {
*st = n->childNum;
*tem = n->tSum;
return;
}
else {
//part with memory issue
long long* tl = new long long;
int* sl = new int;
*tl = 0; *sl = 0;
if (l) Search(x1, x2, y1, y2, l, sl, tl);
*st += (*sl );
*tem += (*tl);
delete tl, sl;
long long* tr = new long long;
int* sr = new int;
if (r) Search(x1, x2, y1, y2, r, sr, tr);
*st += (*sr);
*tem += (*tr);
delete tr, sr;
if (nx >= x1 && nx <= x2 && ny >= y1 && ny <= y2) {
*st += 1;
*tem += n->t;
}
//this goes OK
long long tl = 0;
int sl = 0;
if (l) Search(x1, x2, y1, y2, l, &sl, &tl);
*st += (sl);
*tem += (tl);
long long tr = 0;
int sr = 0;
if (r) Search(x1, x2, y1, y2, r, &sr, &tr);
*st += (sr);
*tem += (tr);
if (nx >= x1 && nx <= x2 && ny >= y1 && ny <= y2) {
*st += 1;
*tem += n->t;
}
}
return;
}
感谢@nwp,我意识到这是一个微不足道的问题。
原始代码不起作用的原因是delete
的优先级高于逗号,所以delete a, b, c;
与(delete a), b, c
相同,所以,
delete a,b,c;
只删除a。
同样,cin >> a,b;
与cin >> a;
相同
检查this