Submission #1773369

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Source Code Expand

#include <cstdio>
#include <algorithm>
using namespace std;

#define iter(i, n) for (int i = 1; i <= n; ++i)
#define forw(i, a, b) for (int i = a; i <= b; ++i)

const int mod = 1e9 + 7;
const int NR = 4010;

int n, m, K;
int f[NR][NR];

int main() {
	scanf("%d%d%d", &n, &m, &K);
	int N = n + m + 2, ans = 0;
	f[0][0] = 1; iter(i, n) f[0][i] = 1;
	iter(i, N) {
		forw(j, 0, n) {
			f[i][j] = (f[i - 1][j] - (j - K < 0 ? 0 : f[i - 1][j - K]) + mod) % mod;
			if (j) f[i][j] = (f[i][j] + f[i][j - 1]) % mod;

			int t = i * (K - 1) - j;
			if (j > 0 && j % (K - 1) == n % (K - 1) && t <= m - 1 && t % (K - 1) == (m - 1) % (K - 1)) {
				ans = (0ll + ans + f[i - 1][j - 1] - (j - K < 0 ? 0 : f[i - 1][j - K]) + mod) % mod;
//				printf("!%d %d\n", i, j);
			}

		//	printf("f[%d][%d]=%d\n", i, j, f[i][j]);
		}
	}

	printf("%d\n", ans);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:15:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &m, &K);
                             ^

Judge Result