#include <bits/stdc++.h>
/// based on https://sltechnicalacademy.com/apio-2019-problems-solutions/
using namespace std;
typedef pair<int,int> ii;
int n,q;
char str[300005];
struct seg{
int s, e, t;
bool operator<(const seg &i)const{
return s < i.s;
}
};
struct evt{
int s, e, t, type;
bool operator<(const evt &i)const{
return ii(s,e) < ii(i.s,i.e);
}
};
int ans[300005];
vector<evt> ev;
set<seg> s;
struct fenwick{
int a[300005];
void add(int x, int v){
while (x < 300005){
a[x] += v;
x += x&-x;
}
}
int qu(int x){
int ret = 0;
while (x){
ret += a[x];
x -= x&-x;
}
return ret;
}
}fw;
void solve(int l, int r){
if (l == r) return;
//printf("solving (%d %d)\n",l,r);
int m = (l+r)/2;
solve(l,m);
solve(m+1,r);
vector<evt> up, qu;
for (int i = l; i <= m; i++){
//printf("%d %d %d %d %d\n",i,ev[i].s, ev[i].e, ev[i].t, ev[i].type);
if (ev[i].type == 1){
up.push_back(ev[i]);
}
}
for (int i = m+1; i <= r; i++){
//printf("%d %d %d %d %d\n",i,ev[i].s, ev[i].e, ev[i].t, ev[i].type);
if (ev[i].type == 2){
qu.push_back(ev[i]);
}
}
for (auto x : up){
//printf("update %d %d %d\n",x.s,x.e,x.t);
}
for (auto x : qu){
//printf("query %d %d %d\n",x.s,x.e,x.t);
}
sort(up.begin(),up.end());
sort(qu.begin(),qu.end());
int i = 0;
for (auto Q : qu){
while (i < up.size() && up[i].s <= Q.s){
fw.add(up[i].e, up[i].t);
i++;
}
ans[Q.t] += fw.qu(Q.e);
}
for (int j = 0; j < i; j++){
fw.add(up[j].e, -up[j].t);
}
//printf("end solve (%d %d)\n",l,r);
}
void addrange(int s, int e, int v){
ev.push_back({s,s,v,1});
ev.push_back({s,e+1,-v,1});
}
int main(){
scanf("%d%d", &n,&q);
scanf("%s",str+1);
for (int i = 1; i <= n; i++){
if (str[i] == '1'){
int e = i;
while (e <= n && str[e] == '1') e++;
s.insert({i,e-1,0});
i = e-1;
}
}
for (int i = 0; i < q; i++){
string Qs;
cin >> Qs;
if (Qs == "toggle"){
int x; scanf("%d",&x);
if (str[x] == '0'){
int st = x, ed = x;
auto it = s.lower_bound({x+1, -1, -1});
if (it != s.end() && it->s == x+1){
addrange(it->s, it->e, i+1 - it->t);
ed = it->e;
it = s.erase(it);
}
if (it != s.begin() && prev(it)->e == x-1){
--it;
addrange(it->s, it->e, i+1 - it->t);
st = it->s;
it = s.erase(it);
}
s.insert({st,ed,i+1});
}
else{
auto it = --s.lower_bound({x+1, -1, -1});
addrange(it->s, it->e, i+1 - it->t);
int S = it->s;
int E = it->e;
s.erase(it);
if (S < x) s.insert({S,x-1,i+1});
if (x < E) s.insert({x+1,E,i+1});
}
str[x] ^= 1;
ans[i] = -1;
}
else{
int a,b; scanf("%d%d",&a,&b);
b--;
ev.push_back({a,b,i,2});
auto it = s.lower_bound({a+1,-1,-1});
if (it != s.begin()){
--it;
if (it->s <= a && b <= it->e){
//printf("found existing range %d %d %d\n",it->s,it->e,it->t);
ans[i] += i+1-it->t;
}
}
}
}
solve(0, ev.size()-1);
for (int i = 0; i < q; i++){
if (ans[i] != -1) printf("%d\n",ans[i]);
}
}
Compilation message
street_lamps.cpp: In function 'void solve(int, int)':
street_lamps.cpp:63:15: warning: variable 'x' set but not used [-Wunused-but-set-variable]
63 | for (auto x : up){
| ^
street_lamps.cpp:66:15: warning: variable 'x' set but not used [-Wunused-but-set-variable]
66 | for (auto x : qu){
| ^
street_lamps.cpp:73:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<evt>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
73 | while (i < up.size() && up[i].s <= Q.s){
| ~~^~~~~~~~~~~
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:94:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
94 | scanf("%d%d", &n,&q);
| ~~~~~^~~~~~~~~~~~~~~
street_lamps.cpp:95:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
95 | scanf("%s",str+1);
| ~~~~~^~~~~~~~~~~~
street_lamps.cpp:108:25: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
108 | int x; scanf("%d",&x);
| ~~~~~^~~~~~~~~
street_lamps.cpp:138:27: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
138 | int a,b; scanf("%d%d",&a,&b);
| ~~~~~^~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
1 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
1 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
552 ms |
14948 KB |
Output is correct |
2 |
Correct |
564 ms |
15084 KB |
Output is correct |
3 |
Correct |
589 ms |
15216 KB |
Output is correct |
4 |
Correct |
646 ms |
21288 KB |
Output is correct |
5 |
Correct |
722 ms |
22668 KB |
Output is correct |
6 |
Correct |
565 ms |
22996 KB |
Output is correct |
7 |
Correct |
340 ms |
12928 KB |
Output is correct |
8 |
Correct |
334 ms |
12912 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
2 ms |
460 KB |
Output is correct |
3 |
Correct |
2 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
660 ms |
27124 KB |
Output is correct |
6 |
Correct |
770 ms |
27340 KB |
Output is correct |
7 |
Correct |
730 ms |
22748 KB |
Output is correct |
8 |
Correct |
378 ms |
12860 KB |
Output is correct |
9 |
Correct |
201 ms |
9028 KB |
Output is correct |
10 |
Correct |
234 ms |
11736 KB |
Output is correct |
11 |
Correct |
239 ms |
11720 KB |
Output is correct |
12 |
Correct |
370 ms |
12856 KB |
Output is correct |
13 |
Correct |
374 ms |
12924 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
332 KB |
Output is correct |
2 |
Correct |
1 ms |
332 KB |
Output is correct |
3 |
Correct |
1 ms |
332 KB |
Output is correct |
4 |
Correct |
2 ms |
332 KB |
Output is correct |
5 |
Correct |
474 ms |
18864 KB |
Output is correct |
6 |
Correct |
526 ms |
23708 KB |
Output is correct |
7 |
Correct |
597 ms |
22892 KB |
Output is correct |
8 |
Correct |
608 ms |
30020 KB |
Output is correct |
9 |
Correct |
463 ms |
17676 KB |
Output is correct |
10 |
Correct |
480 ms |
23720 KB |
Output is correct |
11 |
Correct |
465 ms |
17828 KB |
Output is correct |
12 |
Correct |
481 ms |
23560 KB |
Output is correct |
13 |
Correct |
483 ms |
17884 KB |
Output is correct |
14 |
Correct |
475 ms |
23736 KB |
Output is correct |
15 |
Correct |
370 ms |
12856 KB |
Output is correct |
16 |
Correct |
374 ms |
12896 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
1 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
332 KB |
Output is correct |
5 |
Correct |
1 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
552 ms |
14948 KB |
Output is correct |
9 |
Correct |
564 ms |
15084 KB |
Output is correct |
10 |
Correct |
589 ms |
15216 KB |
Output is correct |
11 |
Correct |
646 ms |
21288 KB |
Output is correct |
12 |
Correct |
722 ms |
22668 KB |
Output is correct |
13 |
Correct |
565 ms |
22996 KB |
Output is correct |
14 |
Correct |
340 ms |
12928 KB |
Output is correct |
15 |
Correct |
334 ms |
12912 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
2 ms |
460 KB |
Output is correct |
18 |
Correct |
2 ms |
332 KB |
Output is correct |
19 |
Correct |
1 ms |
332 KB |
Output is correct |
20 |
Correct |
660 ms |
27124 KB |
Output is correct |
21 |
Correct |
770 ms |
27340 KB |
Output is correct |
22 |
Correct |
730 ms |
22748 KB |
Output is correct |
23 |
Correct |
378 ms |
12860 KB |
Output is correct |
24 |
Correct |
201 ms |
9028 KB |
Output is correct |
25 |
Correct |
234 ms |
11736 KB |
Output is correct |
26 |
Correct |
239 ms |
11720 KB |
Output is correct |
27 |
Correct |
370 ms |
12856 KB |
Output is correct |
28 |
Correct |
374 ms |
12924 KB |
Output is correct |
29 |
Correct |
1 ms |
332 KB |
Output is correct |
30 |
Correct |
1 ms |
332 KB |
Output is correct |
31 |
Correct |
1 ms |
332 KB |
Output is correct |
32 |
Correct |
2 ms |
332 KB |
Output is correct |
33 |
Correct |
474 ms |
18864 KB |
Output is correct |
34 |
Correct |
526 ms |
23708 KB |
Output is correct |
35 |
Correct |
597 ms |
22892 KB |
Output is correct |
36 |
Correct |
608 ms |
30020 KB |
Output is correct |
37 |
Correct |
463 ms |
17676 KB |
Output is correct |
38 |
Correct |
480 ms |
23720 KB |
Output is correct |
39 |
Correct |
465 ms |
17828 KB |
Output is correct |
40 |
Correct |
481 ms |
23560 KB |
Output is correct |
41 |
Correct |
483 ms |
17884 KB |
Output is correct |
42 |
Correct |
475 ms |
23736 KB |
Output is correct |
43 |
Correct |
370 ms |
12856 KB |
Output is correct |
44 |
Correct |
374 ms |
12896 KB |
Output is correct |
45 |
Correct |
366 ms |
9632 KB |
Output is correct |
46 |
Correct |
362 ms |
9816 KB |
Output is correct |
47 |
Correct |
381 ms |
11680 KB |
Output is correct |
48 |
Correct |
663 ms |
21124 KB |
Output is correct |
49 |
Correct |
250 ms |
12572 KB |
Output is correct |
50 |
Correct |
263 ms |
12700 KB |
Output is correct |
51 |
Correct |
249 ms |
12556 KB |
Output is correct |
52 |
Correct |
242 ms |
12672 KB |
Output is correct |
53 |
Correct |
248 ms |
12684 KB |
Output is correct |
54 |
Correct |
241 ms |
12664 KB |
Output is correct |