HDU 4296 greedy

Http://acm.hdu.edu.cn/showproblem.php? PID = 1, 4296

Find the minimum value of Sum-W [I]-s [I], O (N)

//#pragma comment(linker, "/STACK:102400000,102400000")#include <cstdio>#include <cstring>#include <algorithm>#include <string>#include <iostream>#include <iomanip>#include <cmath>#include <map>#include <set>#include <queue>using namespace std;#define ls(rt) rt*2#define rs(rt) rt*2+1#define ll long long#define ull unsigned long long#define rep(i,s,e) for(int i=s;i<e;i++)#define repe(i,s,e) for(int i=s;i<=e;i++)#define CL(a,b) memset(a,b,sizeof(a))#define IN(s) freopen(s,"r",stdin)#define OUT(s) freopen(s,"w",stdout)const ll ll_INF = ((ull)(-1))>>1;const double EPS = 1e-8;const double pi = acos(-1.0);const int INF = 100000000;const int MAXN = 100000+20;int w[MAXN],s[MAXN];int main(){    int n,pos;    ll sum,mmin;    while(~scanf("%d",&n))    {        sum=0;        for(int i=0;i<n;i++)            scanf("%d%d",&w[i],&s[i]),sum+=w[i];        mmin=sum-w[0]-s[0];        pos=0;        for(int i=1;i<n;i++)            if(mmin>sum-w[i]-s[i])pos=i,mmin=sum-w[i]-s[i];        printf("%I64d\n",mmin);    }    return 0;}

HDU 4296 greedy