Submission #1689053

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Source Code Expand

#include <bits/stdc++.h>
#include <stdio.h>
using namespace std;

#define INF 2147483647
#define LINF 9223372036854775807
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(), (v).end()

typedef long long ll;
typedef pair<ll, int> P;

int w,h;
ll dp[2][100000];
const ll MOD=1e9+7;

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);

	cin>>w>>h;
	REP(i,w) dp[0][i]=1;
	FOR(i,1,h) {
		dp[i%2][0]=1;
		FOR(j,1,w) {
			dp[i%2][j]=(dp[i%2][j-1]+dp[(i+1)%2][j])%MOD;
		}
	}
	cout<<dp[(h-1)%2][w-1]<<endl;

	return 0;
}

Submission Info

Judge Result