#include <iostream>
using namespace std;
const int MAXN=1e5+10;
int arr[MAXN], pref[MAXN], suf[MAXN];
int tree[4*MAXN][2];
void build_tree(int node, int l, int r) {
if (l==r) {
tree[node][0]=pref[l];
tree[node][1]=suf[l];
return;
}
int mid=(l+r)/2;
build_tree(node*2,l,mid);
build_tree(node*2+1,mid+1,r);
tree[node][0]=min(tree[node*2][0],tree[node*2+1][0]);
tree[node][1]=min(tree[node*2][1],tree[node*2+1][1]);
}
int query(int node, int l, int r, int ql, int qr, int ind) {
if (ql>r || qr<l) return MAXN;
if (l>=ql && r<=qr) return tree[node][ind];
int mid=(l+r)/2;
return min(query(node*2,l,mid,ql,qr,ind),query(node*2+1,mid+1,r,ql,qr,ind));
}
int main () {
ios::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n;
cin >> n;
char ch;
for (int i=1;i<=n;i++) {
cin >> ch;
if (ch=='C') arr[i]=1;
else arr[i]=-1;
}
for (int i=1;i<=n;i++) pref[i]=pref[i-1]+arr[i];
suf[n+1]=0;
for (int i=n;i>=1;i--) suf[i]=suf[i+1]+arr[i];
build_tree(1,1,n);
int q, l, r;
cin >> q;
for (int i=0;i<q;i++) {
cin >> l >> r;
int s1=query(1,1,n,l,r,0)-pref[l-1];
int s2=query(1,1,n,l,r,1)-suf[r+1];
cout << max(0,-min(s1,s2)) << endl;
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
2392 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
2392 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
4 ms |
2392 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |