#include <bits/stdc++.h>
#define DIMN 500010
using namespace std;
int vi[DIMN] , sp[DIMN] , tt[DIMN] , next_c[DIMN];
map <int , int> mp;
pair <int , int> rmq[20][DIMN];
int srmq[20][DIMN];
vector <int> v[DIMN];
int aint[4 * DIMN];
int sol;
void build (int nod ,int st,int dr){
int mid = (st + dr)/2;
if (st == dr){
aint[nod] = min(0 , vi[st]);
return;
}
build (2*nod,st,mid);
build (2*nod+1,mid+1,dr);
aint[nod] = min(aint[2 * nod + 1] , sp[dr] - sp[mid] + aint[2 * nod]);
}
void query (int nod , int st , int dr , int l , int r){
int mid = (st + dr)/2;
if (l <= st && dr <= r){ /// sunt in interval bun
sol = min(sol , aint[nod] + sp[r] - sp[dr]);
}
else {
if (mid + 1 <= r)
query(2 * nod + 1 , mid + 1 , dr , l , r);
if (l <= mid)
query(2 * nod , st , mid , l , r);
}
}
int main()
{
FILE *fin = stdin;
//FILE *ans = fopen ("idk.in","r");
FILE *fout = stdout;
int n, q , i , l , r , nod , j , vecin , maxi , fth , inc = 0;
char c;
fscanf (fin,"%d\n",&n);
for (i = 1 ; i <= n ; i++){
c=fgetc (fin);
if (c == 'C')
vi[i] = 1;
else vi[i] = -1;
sp[i] = vi[i] + sp[i - 1];
}
next_c[n + 1] = n + 1;
for (i = n ; i ; i--){
if (vi[i] == 1)
next_c[i] = i;
else next_c[i] = next_c[i + 1];
}
for (i = n ; i ; i--){
/// sp[j] - sp[i - 1] = -1
/// sp[j] = -1 + sp[i - 1]
if (vi[i] == -1){
v[i + 1].push_back(i);
tt[i] = i + 1;
}
else {
if (mp[sp[i - 1] - 1] != 0){
v[mp[sp[i - 1] - 1]].push_back(i); /// intervalul i...chestie are suma -1
tt[i] = mp[sp[i - 1] - 1];
}
else {
v[n + 1].push_back(i); /// n + 1 = nod fictiv radacina
tt[i] = n + 1;
}
}
mp[sp[i]] = i;
}
build (1 , 1 , n);
/// vezi ce valoare dai muchiilor
for (nod = 1 ; nod <= n + 1 ; nod++){ /// nod este tatal
for (j = 0 ; j < v[nod].size() ; j++){
vecin = v[nod][j];
//printf ("%d %d " , vecin , nod);
if (nod - vecin > 1 || (nod - vecin == 1 && vi[nod] == -1))
srmq[0][vecin] = 1; /// altfel e 0
if (nod - vecin == 1 && vi[vecin] == -1){
rmq[0][vecin] = make_pair(nod , 0);
//printf ("%d\n", 0);
continue;
}
sol = DIMN;
query(1 , 1 , n , vecin , min(n , nod));
if (nod != n + 1){
rmq[0][vecin] = make_pair(nod , -sol - 1);
//printf ("%d\n", -sol - 1);
}
else {
rmq[0][vecin] = make_pair(nod , -sol);
//printf ("%d\n",-sol);
}
}
}
for (i = 1 ; i < 20 ; i++){
for (j = 1 ; j <= n ; j++){
rmq[i][j].first = rmq[i - 1][rmq[i - 1][j].first].first;
rmq[i][j].second = max(rmq[i - 1][j].second , rmq[i - 1][rmq[i - 1][j].first].second);
srmq[i][j] = srmq[i - 1][j] + srmq[i - 1][rmq[i - 1][j].first];
}
}
fscanf (fin,"%d",&q);
int correct , mini = DIMN , li , ri;
int deadd = 0 , ant;
for (int aux = 1 ; aux <= q ; aux++){
fscanf (fin,"%d%d",&l,&r);
/*if (aux == 1597){
printf ("\n");
for (int k = l ; k <= r ; k++)
printf ("%d ", vi[k]);
printf ("\n");
printf ("a");
}*/
li = l;
ri = r;
maxi = 0;
//if (vi[li] == 1)
inc = 0;
//else inc = 0;
l = next_c[l];
if (l > r){
deadd = ri - li + 1;
inc = maxi = 0;
}
else {
deadd = l - li;
while (tt[l] <= r){
if (srmq[0][l]){
if (l + 1 != tt[l])
maxi = max(maxi - (sp[tt[l] - 1] - sp[l - 1]) , rmq[0][l].second);
}
//else {
// maxi = max(maxi - 1 , 0);
//}
inc += srmq[0][l];
//printf ("%d ",maxi);
ant = srmq[0][l];
l = tt[l];
}
/*maxi = 0;
inc = -1;
for (i = 19 ; i >= 0 ; i--){
fth = rmq[i][l].first;
if (fth < r && fth){
maxi = max(maxi , rmq[i][l].second);
l = fth;
inc += (1 << i);
}
}*/
/// l e < r
if (ant)
l++;
if (l <= r){
sol = DIMN;
query (1 , 1 , n , l , r);
maxi = max(maxi - ( sp[r] - sp[l - 1] ) , -sol);
}
}
fscanf (ans, "%d",&correct);
//maxi = max(maxi , - (sp[ri] - sp[li - 1] + inc));
/*if (correct != inc + maxi + deadd){
mini = min(mini , ri - li + 1);
if (ri - li + 1 == 4)
printf ("%d\n",aux);
}*/
fprintf (fout,"%d\n",inc + maxi + deadd);
}
//printf ("%d",mini);
return 0;
}
Compilation message
election.cpp: In function 'int main()':
election.cpp:108:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
108 | for (j = 0 ; j < v[nod].size() ; j++){
| ~~^~~~~~~~~~~~~~~
election.cpp:233:17: error: 'ans' was not declared in this scope; did you mean 'ant'?
233 | fscanf (ans, "%d",&correct);
| ^~~
| ant
election.cpp:55:53: warning: unused variable 'fth' [-Wunused-variable]
55 | int n, q , i , l , r , nod , j , vecin , maxi , fth , inc = 0;
| ^~~
election.cpp:156:19: warning: unused variable 'mini' [-Wunused-variable]
156 | int correct , mini = DIMN , li , ri;
| ^~~~
election.cpp:57:12: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
57 | fscanf (fin,"%d\n",&n);
| ~~~~~~~^~~~~~~~~~~~~~~
election.cpp:154:12: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
154 | fscanf (fin,"%d",&q);
| ~~~~~~~^~~~~~~~~~~~~
election.cpp:161:16: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
161 | fscanf (fin,"%d%d",&l,&r);
| ~~~~~~~^~~~~~~~~~~~~~~~~~
