40分求调

#include <iostream>
#include <algorithm>
#define Please return
#define AC 0
//#pragma GCC optimize(2)
//#pragma GCC optimize(3)
using namespace std;
const int MAXN = 5e2 + 5, INF = 1e9;
int n, L, c[MAXN], l[MAXN], dp[MAXN];
int sum, ans = INF;

int main() {
	cin >> n >> L;
	for (int i = 1; i <= n; i++) {
		cin >> c[i] >> l[i];
		if (l[i] > L) {
			l[i] = L;
		}
		sum += l[i];
	}
	if (sum < L) {
		cout << "no solution" << endl;
	} else {
		for (int i = 1; i <= 2 * L; i++) {
			dp[i] = INF;
		}
		for (int i = 1; i <= n; i++) {
			for (int j = 2 * L; j >= l[i]; j--) {
				dp[j] = min(dp[j], dp[j - l[i]] + c[i]);
			}
		}
		for (int i = L; i <= 2 * L; i++) {
			ans = min(ans, dp[i]);
		}
		cout << ans << endl;
	}
	Please AC;
}