Codeforces Round 142 (Div. 2) A

Codeforces Round 142 (Div. 2) A.cpp

//By Brickgao
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <vector>
using namespace std;

typedef struct record{
    __int64 x;
    __int64 y;
} record;

record rec[1010];
__int64 s, n;

bool cmp(record a, record b)
{
    return a.x < b.x;
}

int main()
{
    bool flag = true;
    cin >> s >> n;
    for(__int64 i = 0; i < n; i++)
        cin >> rec[i].x >> rec[i].y;
    sort(rec, rec + n, cmp);
    for(__int64 i = 0; i < n; i++)
    {
        if(rec[i].x < s)
            s += rec[i].y;
        else
        {
            flag = false;
            break;
        }
    }
    if(flag)
        cout << "YES" << endl;
    else
        cout << "NO" << endl;
    return 0;
}