第一题帮朋友做的，AC了 LUCKY BOY<zhang.yun.hao@foxmail.com> 16:26:24 #include<iostream> #include<vector> using namespace std; int main() { int n; cin >> n; vector<int> vec; vector<int> dp(n + 1, -1); for (int i = 0; i < n; i++) { int tmp; cin >> tmp; vec.push_back(tmp); } dp[0] = 0; for (int i = 1; i <= n; i++) { int min = 99999; //从i节点之前找到可以跳到i的一个节点,该节点必须可到达，即不为-1 for (int j = 0; j < i; j++) { if (vec[j] >= i - j) { if (min > dp[j] && dp[j] != -1) min = dp[j]; } } dp[i] = (min == 99999 ? -1 : min + 1); } cout << dp[n] << endl; }