Graph, Number Theory, String Hashing Algo added

Number Theory/Fast_Multiply.cpp

@@ -0,0 +1,9 @@
+int fast_multiply(int a,int b,int c){
+	int res=0;
+	while(b){
+		if(b&1)res+=a,res%=c;
+		a+=a,a%=c;
+		b>>=1;
+	}
+	return res;
+}

Number Theory/extended_gcd_recursive.cpp

@@ -0,0 +1,12 @@
+//Extended gcd -> Recursive
+
+tuple<int,int,int> extended_gcd( int a, int b){
+	
+	if( b == 0 ){
+		return {1,0,a};
+	}
+	
+	int x,y,g;
+	tie(x,y,g) = extended_gcd( b , a%b );
+	return {y , x - (a/b)*y , g};
+}

Number Theory/inverse_modulo_array.cpp

@@ -0,0 +1,24 @@
+vector<int> invs( vi& a , int m ){
+	int n = (int)a.size();
+	
+	if( n == 0 ) return {};
+	
+	vector<int> b(n);
+	
+	int v = 1;
+	for(int i = 0 ; i < n ; i++ ){
+		b[i] = v;
+		v = ((long long)v * a[i] ) % m; 
+	}
+	
+	int x = power( v , m - 2 , m ) ;
+	
+	x = (x % m + m ) % m;
+	
+	for(int i = n - 1 ; i >= 0 ; i-- ){
+		b[i] = x * b[i] %m;
+		x = x * a[i] % m;
+	}
+	
+	return b;
+}

Number Theory/modAdd.cpp

@@ -0,0 +1,4 @@
+template<typename T>
+T modAdd(T a,T b,T M=(T)1e9+7){
+	return ((M+a%M)%M+(M+b%M)%M)%M;
+}

Number Theory/modMul.cpp

@@ -0,0 +1,4 @@
+template<typename T>
+T modMul(T a,T b,T M=(int)1e9+7){
+	return ((a%M)*(b%M))%M;
+}

Number Theory/modSub.cpp

@@ -0,0 +1,4 @@
+template<typename T>
+T modSub(T a,T b,T M=(T)1e9+7){
+	return (M+((M+a%M)%M-(M+b%M)%M))%M;
+}