#include <bits/stdc++.h>
#define int long long
using namespace std;
struct DP {
long long minSwaps;
int minGroups, maxGroups;
DP operator + ( DP x ) {
return { minSwaps + x.minSwaps, minGroups + x.minGroups, maxGroups + x.maxGroups };
}
DP operator * ( DP x ) {
if ( minSwaps < x.minSwaps )
return *this;
if ( minSwaps > x.minSwaps )
return x;
return { minSwaps, min( minGroups, x.minGroups ), max( maxGroups, x.maxGroups ) };
}
};
const int MAX_N = 1e6;
const long long INF = 1e18;
int a[MAX_N + 1], countLowerA[MAX_N + 1];
long long sumA[MAX_N + 1], sumLowerA[MAX_N + 1];
DP dp[MAX_N + 1];
struct func {
long long a, b;
int valmin, valmax;
long long value( long long x ) {
return a * x + b;
}
};
struct CHT {
vector<func> funcs;
vector<long long> start;
vector<int> stack;
DP dppp[MAX_N + 1];
void init() {
for ( int i = 0; i <= MAX_N; i++ )
dppp[i] = { INF, MAX_N + 1, 0 };
funcs.clear();
start.clear();
stack.clear();
}
long double intersection( func f1, func f2 ) {
return ((long double)f2.b - f1.b) / (f1.a - f2.a);
}
void addFunction( func f ) {
int i = funcs.size();
funcs.push_back( f );
start.push_back( 0 );
while ( !stack.empty() && intersection( funcs[i], funcs[stack.back()] ) <= start[stack.back()] )
stack.pop_back();
if ( !stack.empty() ) {
long long x = intersection( funcs[i], funcs[stack.back()] );
if ( intersection( funcs[i], funcs[stack.back()] ) == x && x <= MAX_N )
dppp[x] = dppp[x] * DP{ funcs[stack.back()].value( x ), funcs[stack.back()].valmin, funcs[stack.back()].valmax };
start[i] = ceil( intersection( funcs[i], funcs[stack.back()]) );
}
stack.push_back( i );
}
DP getMin( long long x ) {
int l = -1, r = stack.size();
while ( r - l > 1 ) {
int mid = (l + r) / 2;
if ( start[stack[mid]] > x )
r = mid;
else
l = mid;
}
return DP{ funcs[stack[l]].value( x ), funcs[stack[l]].valmin, funcs[stack[l]].valmax } * dppp[x];
}
} swapFunctions;
void computeDP( int n, long long cost ) {
swapFunctions.init();
swapFunctions.addFunction( { 0, 0, 0, 0 } );
for ( int i = 1; i <= n; i++ ) {
dp[i] = swapFunctions.getMin( i ) + DP{ i * countLowerA[i] - sumLowerA[i] + cost, 1, 1 };
swapFunctions.addFunction( func{ -i, dp[i].minSwaps + sumA[i], dp[i].minGroups, dp[i].maxGroups } );
}
}
signed main() {
int n, k, swaps;
cin >> n >> k;
int countB = 0, countA = 0;
swaps = 0;
for ( int i = 0; i < 2 * n; i++ ) {
char ch;
cin >> ch;
if ( ch == 'A' )
countA++;
else {
countB++;
swaps += max( 0LL, countB - countA );
a[countB] = max( countA, countB );
sumA[countB] = sumA[countB - 1] + a[countB];
countLowerA[a[countB]]++;
sumLowerA[a[countB]] += a[countB];
}
}
for ( int i = 1; i <= n; i++ ) {
countLowerA[i] += countLowerA[i - 1];
sumLowerA[i] += sumLowerA[i - 1];
}
long long leftCost = -1, rightCost = 1e12;
while ( rightCost - leftCost > 1 ) {
long long cost = (leftCost + rightCost) / 2;
computeDP( n, cost );
if ( dp[n].minGroups > k )
leftCost = cost;
else
rightCost = cost;
}
computeDP( n, rightCost );
cout << swaps + dp[n].minSwaps - min( k, dp[n].maxGroups ) * rightCost;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
121 ms |
31324 KB |
Output is correct |
2 |
Correct |
121 ms |
31388 KB |
Output is correct |
3 |
Correct |
122 ms |
31324 KB |
Output is correct |
4 |
Correct |
124 ms |
31396 KB |
Output is correct |
5 |
Correct |
123 ms |
31384 KB |
Output is correct |
6 |
Correct |
127 ms |
31380 KB |
Output is correct |
7 |
Correct |
122 ms |
31320 KB |
Output is correct |
8 |
Correct |
125 ms |
31396 KB |
Output is correct |
9 |
Correct |
123 ms |
31380 KB |
Output is correct |
10 |
Correct |
126 ms |
31324 KB |
Output is correct |
11 |
Correct |
123 ms |
31384 KB |
Output is correct |
12 |
Correct |
121 ms |
31328 KB |
Output is correct |
13 |
Correct |
120 ms |
31324 KB |
Output is correct |
14 |
Correct |
123 ms |
31320 KB |
Output is correct |
15 |
Correct |
124 ms |
31572 KB |
Output is correct |
16 |
Correct |
129 ms |
31324 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
121 ms |
31324 KB |
Output is correct |
2 |
Correct |
121 ms |
31388 KB |
Output is correct |
3 |
Correct |
122 ms |
31324 KB |
Output is correct |
4 |
Correct |
124 ms |
31396 KB |
Output is correct |
5 |
Correct |
123 ms |
31384 KB |
Output is correct |
6 |
Correct |
127 ms |
31380 KB |
Output is correct |
7 |
Correct |
122 ms |
31320 KB |
Output is correct |
8 |
Correct |
125 ms |
31396 KB |
Output is correct |
9 |
Correct |
123 ms |
31380 KB |
Output is correct |
10 |
Correct |
126 ms |
31324 KB |
Output is correct |
11 |
Correct |
123 ms |
31384 KB |
Output is correct |
12 |
Correct |
121 ms |
31328 KB |
Output is correct |
13 |
Correct |
120 ms |
31324 KB |
Output is correct |
14 |
Correct |
123 ms |
31320 KB |
Output is correct |
15 |
Correct |
124 ms |
31572 KB |
Output is correct |
16 |
Correct |
129 ms |
31324 KB |
Output is correct |
17 |
Correct |
120 ms |
31400 KB |
Output is correct |
18 |
Correct |
129 ms |
31324 KB |
Output is correct |
19 |
Correct |
121 ms |
31572 KB |
Output is correct |
20 |
Correct |
129 ms |
31324 KB |
Output is correct |
21 |
Correct |
123 ms |
31324 KB |
Output is correct |
22 |
Correct |
127 ms |
31420 KB |
Output is correct |
23 |
Correct |
120 ms |
31320 KB |
Output is correct |
24 |
Correct |
126 ms |
31324 KB |
Output is correct |
25 |
Correct |
120 ms |
31424 KB |
Output is correct |
26 |
Correct |
125 ms |
31568 KB |
Output is correct |
27 |
Correct |
122 ms |
31324 KB |
Output is correct |
28 |
Correct |
125 ms |
31416 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
121 ms |
31324 KB |
Output is correct |
2 |
Correct |
121 ms |
31388 KB |
Output is correct |
3 |
Correct |
122 ms |
31324 KB |
Output is correct |
4 |
Correct |
124 ms |
31396 KB |
Output is correct |
5 |
Correct |
123 ms |
31384 KB |
Output is correct |
6 |
Correct |
127 ms |
31380 KB |
Output is correct |
7 |
Correct |
122 ms |
31320 KB |
Output is correct |
8 |
Correct |
125 ms |
31396 KB |
Output is correct |
9 |
Correct |
123 ms |
31380 KB |
Output is correct |
10 |
Correct |
126 ms |
31324 KB |
Output is correct |
11 |
Correct |
123 ms |
31384 KB |
Output is correct |
12 |
Correct |
121 ms |
31328 KB |
Output is correct |
13 |
Correct |
120 ms |
31324 KB |
Output is correct |
14 |
Correct |
123 ms |
31320 KB |
Output is correct |
15 |
Correct |
124 ms |
31572 KB |
Output is correct |
16 |
Correct |
129 ms |
31324 KB |
Output is correct |
17 |
Correct |
120 ms |
31400 KB |
Output is correct |
18 |
Correct |
129 ms |
31324 KB |
Output is correct |
19 |
Correct |
121 ms |
31572 KB |
Output is correct |
20 |
Correct |
129 ms |
31324 KB |
Output is correct |
21 |
Correct |
123 ms |
31324 KB |
Output is correct |
22 |
Correct |
127 ms |
31420 KB |
Output is correct |
23 |
Correct |
120 ms |
31320 KB |
Output is correct |
24 |
Correct |
126 ms |
31324 KB |
Output is correct |
25 |
Correct |
120 ms |
31424 KB |
Output is correct |
26 |
Correct |
125 ms |
31568 KB |
Output is correct |
27 |
Correct |
122 ms |
31324 KB |
Output is correct |
28 |
Correct |
125 ms |
31416 KB |
Output is correct |
29 |
Correct |
137 ms |
31832 KB |
Output is correct |
30 |
Correct |
144 ms |
31836 KB |
Output is correct |
31 |
Correct |
137 ms |
31836 KB |
Output is correct |
32 |
Correct |
132 ms |
31836 KB |
Output is correct |
33 |
Correct |
143 ms |
31832 KB |
Output is correct |
34 |
Correct |
139 ms |
31832 KB |
Output is correct |
35 |
Correct |
135 ms |
31832 KB |
Output is correct |
36 |
Correct |
141 ms |
31836 KB |
Output is correct |
37 |
Correct |
143 ms |
31836 KB |
Output is correct |
38 |
Correct |
140 ms |
31836 KB |
Output is correct |
39 |
Correct |
143 ms |
31832 KB |
Output is correct |
40 |
Correct |
138 ms |
31832 KB |
Output is correct |
41 |
Correct |
139 ms |
31832 KB |
Output is correct |
42 |
Correct |
138 ms |
31680 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
121 ms |
31324 KB |
Output is correct |
2 |
Correct |
121 ms |
31388 KB |
Output is correct |
3 |
Correct |
122 ms |
31324 KB |
Output is correct |
4 |
Correct |
124 ms |
31396 KB |
Output is correct |
5 |
Correct |
123 ms |
31384 KB |
Output is correct |
6 |
Correct |
127 ms |
31380 KB |
Output is correct |
7 |
Correct |
122 ms |
31320 KB |
Output is correct |
8 |
Correct |
125 ms |
31396 KB |
Output is correct |
9 |
Correct |
123 ms |
31380 KB |
Output is correct |
10 |
Correct |
126 ms |
31324 KB |
Output is correct |
11 |
Correct |
123 ms |
31384 KB |
Output is correct |
12 |
Correct |
121 ms |
31328 KB |
Output is correct |
13 |
Correct |
120 ms |
31324 KB |
Output is correct |
14 |
Correct |
123 ms |
31320 KB |
Output is correct |
15 |
Correct |
124 ms |
31572 KB |
Output is correct |
16 |
Correct |
129 ms |
31324 KB |
Output is correct |
17 |
Correct |
120 ms |
31400 KB |
Output is correct |
18 |
Correct |
129 ms |
31324 KB |
Output is correct |
19 |
Correct |
121 ms |
31572 KB |
Output is correct |
20 |
Correct |
129 ms |
31324 KB |
Output is correct |
21 |
Correct |
123 ms |
31324 KB |
Output is correct |
22 |
Correct |
127 ms |
31420 KB |
Output is correct |
23 |
Correct |
120 ms |
31320 KB |
Output is correct |
24 |
Correct |
126 ms |
31324 KB |
Output is correct |
25 |
Correct |
120 ms |
31424 KB |
Output is correct |
26 |
Correct |
125 ms |
31568 KB |
Output is correct |
27 |
Correct |
122 ms |
31324 KB |
Output is correct |
28 |
Correct |
125 ms |
31416 KB |
Output is correct |
29 |
Correct |
137 ms |
31832 KB |
Output is correct |
30 |
Correct |
144 ms |
31836 KB |
Output is correct |
31 |
Correct |
137 ms |
31836 KB |
Output is correct |
32 |
Correct |
132 ms |
31836 KB |
Output is correct |
33 |
Correct |
143 ms |
31832 KB |
Output is correct |
34 |
Correct |
139 ms |
31832 KB |
Output is correct |
35 |
Correct |
135 ms |
31832 KB |
Output is correct |
36 |
Correct |
141 ms |
31836 KB |
Output is correct |
37 |
Correct |
143 ms |
31836 KB |
Output is correct |
38 |
Correct |
140 ms |
31836 KB |
Output is correct |
39 |
Correct |
143 ms |
31832 KB |
Output is correct |
40 |
Correct |
138 ms |
31832 KB |
Output is correct |
41 |
Correct |
139 ms |
31832 KB |
Output is correct |
42 |
Correct |
138 ms |
31680 KB |
Output is correct |
43 |
Correct |
351 ms |
38604 KB |
Output is correct |
44 |
Correct |
535 ms |
42744 KB |
Output is correct |
45 |
Correct |
524 ms |
41676 KB |
Output is correct |
46 |
Correct |
366 ms |
41924 KB |
Output is correct |
47 |
Correct |
418 ms |
41872 KB |
Output is correct |
48 |
Correct |
499 ms |
42692 KB |
Output is correct |
49 |
Correct |
469 ms |
42956 KB |
Output is correct |
50 |
Correct |
519 ms |
42692 KB |
Output is correct |
51 |
Correct |
533 ms |
42956 KB |
Output is correct |
52 |
Correct |
480 ms |
43212 KB |
Output is correct |
53 |
Correct |
490 ms |
42272 KB |
Output is correct |
54 |
Correct |
540 ms |
41668 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
121 ms |
31324 KB |
Output is correct |
2 |
Correct |
121 ms |
31388 KB |
Output is correct |
3 |
Correct |
122 ms |
31324 KB |
Output is correct |
4 |
Correct |
124 ms |
31396 KB |
Output is correct |
5 |
Correct |
123 ms |
31384 KB |
Output is correct |
6 |
Correct |
127 ms |
31380 KB |
Output is correct |
7 |
Correct |
122 ms |
31320 KB |
Output is correct |
8 |
Correct |
125 ms |
31396 KB |
Output is correct |
9 |
Correct |
123 ms |
31380 KB |
Output is correct |
10 |
Correct |
126 ms |
31324 KB |
Output is correct |
11 |
Correct |
123 ms |
31384 KB |
Output is correct |
12 |
Correct |
121 ms |
31328 KB |
Output is correct |
13 |
Correct |
120 ms |
31324 KB |
Output is correct |
14 |
Correct |
123 ms |
31320 KB |
Output is correct |
15 |
Correct |
124 ms |
31572 KB |
Output is correct |
16 |
Correct |
129 ms |
31324 KB |
Output is correct |
17 |
Correct |
120 ms |
31400 KB |
Output is correct |
18 |
Correct |
129 ms |
31324 KB |
Output is correct |
19 |
Correct |
121 ms |
31572 KB |
Output is correct |
20 |
Correct |
129 ms |
31324 KB |
Output is correct |
21 |
Correct |
123 ms |
31324 KB |
Output is correct |
22 |
Correct |
127 ms |
31420 KB |
Output is correct |
23 |
Correct |
120 ms |
31320 KB |
Output is correct |
24 |
Correct |
126 ms |
31324 KB |
Output is correct |
25 |
Correct |
120 ms |
31424 KB |
Output is correct |
26 |
Correct |
125 ms |
31568 KB |
Output is correct |
27 |
Correct |
122 ms |
31324 KB |
Output is correct |
28 |
Correct |
125 ms |
31416 KB |
Output is correct |
29 |
Correct |
137 ms |
31832 KB |
Output is correct |
30 |
Correct |
144 ms |
31836 KB |
Output is correct |
31 |
Correct |
137 ms |
31836 KB |
Output is correct |
32 |
Correct |
132 ms |
31836 KB |
Output is correct |
33 |
Correct |
143 ms |
31832 KB |
Output is correct |
34 |
Correct |
139 ms |
31832 KB |
Output is correct |
35 |
Correct |
135 ms |
31832 KB |
Output is correct |
36 |
Correct |
141 ms |
31836 KB |
Output is correct |
37 |
Correct |
143 ms |
31836 KB |
Output is correct |
38 |
Correct |
140 ms |
31836 KB |
Output is correct |
39 |
Correct |
143 ms |
31832 KB |
Output is correct |
40 |
Correct |
138 ms |
31832 KB |
Output is correct |
41 |
Correct |
139 ms |
31832 KB |
Output is correct |
42 |
Correct |
138 ms |
31680 KB |
Output is correct |
43 |
Correct |
351 ms |
38604 KB |
Output is correct |
44 |
Correct |
535 ms |
42744 KB |
Output is correct |
45 |
Correct |
524 ms |
41676 KB |
Output is correct |
46 |
Correct |
366 ms |
41924 KB |
Output is correct |
47 |
Correct |
418 ms |
41872 KB |
Output is correct |
48 |
Correct |
499 ms |
42692 KB |
Output is correct |
49 |
Correct |
469 ms |
42956 KB |
Output is correct |
50 |
Correct |
519 ms |
42692 KB |
Output is correct |
51 |
Correct |
533 ms |
42956 KB |
Output is correct |
52 |
Correct |
480 ms |
43212 KB |
Output is correct |
53 |
Correct |
490 ms |
42272 KB |
Output is correct |
54 |
Correct |
540 ms |
41668 KB |
Output is correct |
55 |
Correct |
3434 ms |
107808 KB |
Output is correct |
56 |
Correct |
5283 ms |
137328 KB |
Output is correct |
57 |
Correct |
5468 ms |
127940 KB |
Output is correct |
58 |
Correct |
2873 ms |
128444 KB |
Output is correct |
59 |
Correct |
3801 ms |
134008 KB |
Output is correct |
60 |
Correct |
5088 ms |
135780 KB |
Output is correct |
61 |
Correct |
4944 ms |
135984 KB |
Output is correct |
62 |
Correct |
5315 ms |
127824 KB |
Output is correct |
63 |
Correct |
5459 ms |
128660 KB |
Output is correct |
64 |
Correct |
5054 ms |
136624 KB |
Output is correct |
65 |
Correct |
5016 ms |
135772 KB |
Output is correct |
66 |
Correct |
5789 ms |
127908 KB |
Output is correct |
67 |
Correct |
5047 ms |
136880 KB |
Output is correct |