oj.uz

Submission #734121

# Submission time Handle Problem Language Result Execution time Memory
734121 2023-05-01T18:05:45 Z racsosabe Modsum (NOI12_modsum) C++14
0 / 25
 1 ms 468 KB 
#include <bits/stdc++.h>
using namespace std;

const int MOD = 1e9 + 7;
const int N = 100000 + 5;

int add(int a, int b){
    return (a + b) % MOD;
}

int mul(long long a, long long b){
    return (a * b) % MOD;
}

int n;
long long L[N];
long long R[N];
bool vis[N][5][5];
int memo[N][5][5];

long long get_cnt(int rem, long long l, long long r){
    if(l % 5 <= rem) l += rem - l % 5;
    else l += rem - l % 5 + 5;
    if(r % 5 >= rem) r += rem - l % 5;
    else r += rem - l % 5 - 5;
    return l <= r ? (r - l) / 5 + 1 : 0;
}

int DP(int pos, int sum_sq, int sum){
	if(pos == n) return ((sum_sq + 1) * (sum_sq + 1) + 4) % 5 + 1;
	if(vis[pos][sum_sq][sum]) return memo[pos][sum_sq][sum];
	int res = 0;
	for(int x = 0; x < 5; x++){
		int new_sum_sq = (sum_sq + 2 * sum * x + x * x) % 5;
		int new_sum = (sum + x) % 5;
		int Q = get_cnt(x, L[pos], R[pos]) % MOD;
		res = add(res, mul(Q, DP(pos + 1, new_sum_sq, new_sum)));
	}
	vis[pos][sum_sq][sum] = true;
	return memo[pos][sum_sq][sum] = res;
}

int main() {
	scanf("%d", &n);
	for(int i = 0; i < n; i++) scanf("%lld %lld", L + i, R + i);
	printf("%d\n", DP(0, 0, 0));
	return 0;
}

Compilation message

modsum.cpp: In function 'int main()':
modsum.cpp:44:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
modsum.cpp:45:34: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |  for(int i = 0; i < n; i++) scanf("%lld %lld", L + i, R + i);
      |                             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 1 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 1 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 1 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 468 KB Output isn't correct
2 Halted 0 ms 0 KB -