POJ 1179 DP

// DP 

#include<iostream>

#include<string>

#include<cstdio>

#include<cstdlib>

#include<cstring>

#include<cmath>

#include<algorithm>

#include<map>

#include<vector>

#define MAXN 55

#define MAXM 55

#define MOD 10000

#define inf 1e15

#define eps 1e-9

#define LL long long 

using namespace std;

int n, idx[MAXN], len;

char op[MAXN][5];

LL v[MAXN], dp[MAXN][MAXN][2];

void solve(int i, int s, int j, LL &minf, LL &maxf) {

int r = (i + s - 1) % n + 1;

LL a = dp[i][s][0], b = dp[i][s][1], c = dp[r][j - s][0], d = dp[r][j - s][1], tmp[4];

if (op[r][0] == 't') {

minf = a + c, maxf = b + d;

} else {

tmp[0] = a * c, tmp[1] = a * d, tmp[2] = b * c, tmp[3] = b * d;

sort(tmp, tmp + 4);

minf = tmp[0], maxf = tmp[3];

}

} 

int a[3];

int main() {

//freopen("in.txt","r",stdin);

//freopen("out.txt", "w", stdout);

scanf("%d", &n);

for (int i = 1; i <= n; i++)

scanf("%s %lld", op[i], &v[i]);

for (int i = 1; i <= n; i++) {

for (int j = 1; j <= n; j++) {

dp[i][j][0] = (LL)inf, dp[i][j][1] = -(LL)inf;

}

}

for (int i = 1; i <= n; i++) dp[i][1][0] = dp[i][1][1] = v[i]; 

LL minf, maxf;

bool flag = false;

for (int j = 2; j <= n; j++) { 

for (int i = 1; i <= n; i++) {

for (int s = 1; s < j; s++) {

solve(i, s, j, minf, maxf);

dp[i][j][0] = min(dp[i][j][0], minf);

dp[i][j][1] = max(dp[i][j][1], maxf);

}

}

}

LL ans = dp[1][n][1];

idx[len = 1] = 1;

for (int i = 2; i <= n; i++) {

if (ans == dp[i][n][1]) {

idx[++len] = i;

} else if (dp[i][n][1] > ans) {

ans = dp[i][n][1];

idx[len = 1] = i;

}

}

sort(idx + 1, idx + len + 1);

printf("%lld\n", ans);

for (int i = 1; i <= len; i++) {

if (i != 1) putchar(' ');

printf("%d", idx[i]);

}

puts("");

    return 0;

}