hdoj/section3-7/main.cpp

#include <iostream>
#include <algorithm>

using namespace std;

struct Box {
    int Ai;
    int Bi;
};

bool compare(Box a, Box b) {
    return a.Ai-a.Bi < b.Ai - b.Bi;
}

bool judge(int V, int N, Box *boxes) {
    sort(boxes, boxes + N, compare);
    for (int i = 0; i < N; i++) {
        if (boxes[i].Bi > V || boxes[i].Ai > V) {
            return false;
        }
        V -= boxes[i].Ai;
    }
    return true;
}

int main() {
    int T, V, N;
    Box *boxes;
    while (cin >> T) {
        for (int i = 0; i < T; i++) {
            cin >> V >> N;
            boxes = new Box[N];
            for (int j = 0; j < N; j++) {
                Box box;
                cin >> box.Ai >> box.Bi;
                boxes[j] = box;
            }
            cout << (judge(V, N, boxes) ? "Yes" : "No") << endl;
            free(boxes);
        }
    }
    return 0;
}