Submission #1552034

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Source Code Expand

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<set>
#include<map>
#include<cmath>

using namespace std;

const int MAXN = 200005;
const int INF = 1000000007;

int n, ind;
int lef[MAXN], rig[MAXN], dp[MAXN], mini[MAXN], suf[MAXN], pot[MAXN];
pair <int, int> pii[MAXN], l[MAXN];
set <int> s;

int add (int a, int b) {
    if (a+b>=INF) return a+b-INF; return a+b;
}

int sub (int a, int b) {
    if (a-b<0) return a-b+INF; return a-b;
}

int main () {
    pot[0]=1;
    cin >> n;
    for (int i=0; i<n; i++) {
        pot[i+1]=add(pot[i], pot[i]);
        mini[i]=INF;
        int xx, vv;
        scanf("%d%d", &xx, &vv);
        pii[i]=make_pair(xx, vv);
    }
    sort(pii, pii+n);
    for (int i=0; i<n; i++) {
        l[i]=make_pair(pii[i].second, i);
    }
    sort(l, l+n);
    ind=-INF;
    for (int i=0; i<n; i++) {
        ind=max(ind, l[i].second);
        rig[i]=ind;
    }
    ind=INF;
    for (int i=n-1; i>=0; i--) {
        ind=min(ind, l[i].second);
        lef[i]=ind;
    }
    for (int i=0; i<n; i++) {
        mini[lef[i]]=min(mini[lef[i]], rig[i]);
    }
    dp[n]=suf[n]=1, ind=INF;
    for (int i=n-1; i>=0; i--) {
        ind=min(ind, mini[i]);
        if (ind==INF) {
            dp[i]=pot[n-i];
        } else {
            dp[i]=suf[i+1]-suf[ind+2];
        }
        suf[i]=add(suf[i+1], dp[i]);
    }
    cout << dp[0];
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:33:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &xx, &vv);
                                ^

Judge Result