int dp[305][15];

int find(vector<int> &diff, int d, int i) {

if(d == 1) {

if(i == diff.size()) {

return INT_MAX / 4;

}

int mx = -1;

for(int j = i; j < diff.size(); j++) {

mx = max(diff[j], mx);

}

return mx;

}

if(dp[i][d] != -1) {

return dp[i][d];

}

int mx = -1;

int ans = INT_MAX / 2;

for(int j = i; j < diff.size() - d + 1; j++) {

mx = max(diff[j], mx);

ans = min(ans, mx + find(diff, d - 1, j + 1));

}

return dp[i][d] = ans;

}

int minDifficulty(vector<int>& jobDifficulty, int d) {

memset(dp, -1, sizeof dp);

int ans = find(jobDifficulty, d, 0);

return (ans >= INT_MAX / 2 ? -1 : ans);

}