uva 10817

Problem D: Headmaster's Headache
Time limit: 2 seconds

The headmaster of Spring Field School is considering employing some new teachers for certain subjects. There are a number of teachers applying for the posts. Each teacher is able to teach one or more subjects. The headmaster wants to select applicants so that each subject is taught by at least two teachers, and the overall cost is minimized.

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

const int MAX_N = 105;
const int INF = 7000000;
int S, M, N;
int ns1 = 0 , ns2 = 0;
int s[MAX_N], prize[MAX_N];
int dp[1 << 9][1 << 9];

void solve() {
dp[ns1][ns2] = prize[0];
dp[ns2][ns1] = prize[0];
for(int i = 1; i <= N; ++i) {
for(int s1 = (1 << S) - 1; s1 >= 0; --s1) {
for(int s2 = (1 << S) - 1; s2 >= 0; --s2) {
if(dp[s1][s2] != INF) {
dp[s1 | s[i]][s1 & s[i] | s2] =
min(dp[s1 | s[i]][s1 & s[i] | s2]
, dp[s1][s2] + prize[i]);

dp[s2 & s[i] | s1][s2 | s[i]] =
min(dp[s2 & s[i] | s1][s2 | s[i]]
, dp[s1][s2] + prize[i]);
}
}
}
}
}

int main()
{
//freopen("sw.in","r",stdin);
while(~scanf("%d%d%d", &S, &M, &N) && (S + M + N)) {
ns1 = 0; ns2 = 0;
for(int i = 0; i < (1 << S); ++i)
for(int j = 0; j < (1 << S); ++j) dp[i][j] = INF;
memset(prize, 0, sizeof(prize));
memset(s, 0, sizeof(s));

for(int i = 1; i <= M; ++i) {
int ch, v;
char c;
scanf("%d%d%c",&v, &ch, &c);
prize[0] += v;
ns2 |=  ns1 & (1 << (ch - 1));
ns1 |= 1 << (ch - 1);

while(c != '\n') {
scanf("%d%c", &ch, &c);
ns2 |=  ns1 & (1 << (ch - 1));
ns1 |= 1 << (ch - 1);
}

}

for(int i = 1; i <= N; ++i) {
int ch;
char c;
scanf("%d%d%c", &prize[i], &ch, &c);
s[i] |=  1 << (ch - 1);
while(c != '\n') {
scanf("%d%c", &ch, &c);
s[i] |= 1 << (ch - 1);
}
}

solve();
printf("%d\n", dp[(1 << S) - 1][(1 << S) - 1]);
}
return 0;
}

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