ncrMod

{
	"": {
		"prefix": "cd_ncrMod",
		"body": [
			"// -----------------------------------------------------------------------------------------------",
			"const int N = 2e5 + 10;",
			"vector<int> fact(N, 1);",
			"",
			"int binExp(int a, int b, int m){",
			" ",
			"  int res = 1;",
			"  ",
			"  while(b){",
			"    if(b & 1) res = (res * 1LL * a) % m;",
			"    a = (a * 1LL * a) % m;",
			"    b = b >> 1;",
			"  }",
			" ",
			"  return res;",
			"}",
			" ",
			"int modInverse(int a, int m){",
			" ",
			"  return binExp(a, m - 2, m);",
			"}",
			"",
			"// call calculateFactorial() in main",
			"void calculateFactorial(int m){",
			" ",
			"  for(int i = 1; i < N; i++){",
			"    fact[i] = (fact[i - 1] * 1LL * i) % m;",
			"  }",
			" ",
			"}",
			" ",
			"int nCrMod(int n, int r, int m){",
			" ",
			"  if(r > n) return 0;",
			" ",
			"  return (fact[n] * 1LL * modInverse((fact[n - r] * 1LL * fact[r]) % m, m)) % m;",
			"}",
			"// -----------------------------------------------------------------------------------------------"
		],
		"description": ""
	}
}