create dev channel

zeta/py/completed/10986.py

@@ -0,0 +1,17 @@
+import sys
+import math
+
+input = sys.stdin.readline
+
+if __name__ == "__main__":
+    N, M = map(int, input().split())
+    A = list(map(int, input().split()))
+    S = [(0, 0)]
+    C = [0] * 1001
+    C[0] = 1
+    for i in range(N):
+        s = ((S[-1][0] + A[i]) % M, i + 1)
+        S.append(s)
+        C[s[0]] += 1
+
+    print(sum([math.comb(c, 2) for c in C]))