Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

N, P = map(int, input().split())
S = list(map(int, list(input().rstrip())))
ans = 0
if P == 2 or P == 5:
    for i in range(N):
        if S[i] % P == 0:
            ans += i + 1
else:
    U = [0] * (N+1)
    count = [0] * P
    count[0] = 1
    factor = 10
    for i in range(N)[::-1]:
        x = S[i] * 10**(N-i-1) + U[i+1]
        U[i] = (S[i] * factor + U[i+1]) % P
        factor = factor * 10 % P
        ans += count[U[i]]
        count[U[i]] += 1
print(ans)


Fixed submission:
import sys
input = sys.stdin.readline

N, P = map(int, input().split())
S = list(map(int, list(input().rstrip())))
ans = 0
if P == 2 or P == 5:
    for i in range(N):
        if S[i] % P == 0:
            ans += i + 1
else:
    U = [0] * (N+1)
    count = [0] * P
    count[0] = 1
    factor = 10
    for i in range(N)[::-1]:
        U[i] = (S[i] * factor + U[i+1]) % P
        factor = factor * 10 % P
        ans += count[U[i]]
        count[U[i]] += 1
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

N, P = map(int, input().split())
S = list(map(int, list(input().rstrip())))
ans = 0
if P == 2 or P == 5:
    for i in range(N):
        if S[i] % P == 0:
            ans += i + 1
else:
    U = [0] * (N+1)
    count = [0] * P
    count[0] = 1
    for i in range(N)[::-1]:
        x = S[i] * 10**(N-i-1) + U[i+1]
        U[i] = (S[i] * 10**(N-i-1) + U[i+1]) % P
        ans += count[U[i]]
        count[U[i]] += 1
print(ans)


Fixed submission:
import sys
input = sys.stdin.readline

N, P = map(int, input().split())
S = list(map(int, list(input().rstrip())))
ans = 0
if P == 2 or P == 5:
    for i in range(N):
        if S[i] % P == 0:
            ans += i + 1
else:
    U = [0] * (N+1)
    count = [0] * P
    count[0] = 1
    factor = 10
    for i in range(N)[::-1]:
        U[i] = (S[i] * factor + U[i+1]) % P
        factor = factor * 10 % P
        ans += count[U[i]]
        count[U[i]] += 1
print(ans)

Buggy python submission (verdict: Runtime Error):
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define all(x) (x).begin(), (x).end()

int main() {
    int N, P;
    cin >> N >> P;
    string S;
    cin >> S;
    ll count[P];
    memset(count, 0, sizeof(count));
    ll ncount[P];
    ll ans = 0;
    rep(i, N) {
        int d = S.at(i) - '0';
        count[0]++;
        memset(ncount, 0, sizeof(ncount));
        rep(j, P) {
            int nj = (j * 10 + d) % P;
            ncount[nj] += count[j];
        }
        rep(j, P) count[j] = ncount[j];
        ans += count[0];
    }
    cout << ans << endl;
}

Fixed submission:
import sys
input = sys.stdin.readline

N, P = map(int, input().split())
S = list(map(int, list(input().rstrip())))
ans = 0
if P == 2 or P == 5:
    for i in range(N):
        if S[i] % P == 0:
            ans += i + 1
else:
    U = [0] * (N+1)
    count = [0] * P
    count[0] = 1
    factor = 10
    for i in range(N)[::-1]:
        U[i] = (S[i] * factor + U[i+1]) % P
        factor = factor * 10 % P
        ans += count[U[i]]
        count[U[i]] += 1
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
N, P = map(int, input().split())
S = input()
count = [0] * P
ans = 0
for d in S:
    d = int(d)
    count[0] += 1
    ncount = [0] * P
    for i in range(P):
        ni = (i * 10 + d) % P
        ncount[ni] += count[i]
    count = ncount
    ans += count[0]
print(ans)

Fixed submission:
import sys
input = sys.stdin.readline

N, P = map(int, input().split())
S = list(map(int, list(input().rstrip())))
ans = 0
if P == 2 or P == 5:
    for i in range(N):
        if S[i] % P == 0:
            ans += i + 1
else:
    U = [0] * (N+1)
    count = [0] * P
    count[0] = 1
    factor = 10
    for i in range(N)[::-1]:
        U[i] = (S[i] * factor + U[i+1]) % P
        factor = factor * 10 % P
        ans += count[U[i]]
        count[U[i]] += 1
print(ans)