KTLT-chuong6.c

#include <stdio.h>

void PrintASCII() {
    for(int i = 0; i < 256; ++i){
      printf("%d %c\n", i, i);
    }
}

int SumOdd(int n) {
    // 1 3 5 7... 2n+1
    // num-in-range * (start + end) / 2
    return (n+1) * (1 + 2*n+1) / 2;
}

int SumEven(int n) {
    // 2 4 6 8... 2n
    // #num-in-range * (start + end) / 2
    return n * (2 + 2*n) / 2;
}

int Factorial(int n) {
    int result = 1;
    for (int i = 2; i <= n; i++) result *= i;
    return result;
}

int UCLN(int a, int b) {
    while (b != 0) {
        int temp = a;
        a = b;
        b = temp % b;
    }
    return a;
}
int BCNN(int a, int b) {
    return a*b / UCLN(a, b);
}

void HCN_Dac(int d, int r) {
    for (int i = 0; i < r; i++) {
        for (int j = 0; j < d; j++) {
            printf("*");
        }
        printf("\n");
    }
}

void HCN_Rong(int d, int r) {
    for (int i = 1; i <= r; i++) {
        for (int j = 1; j <= d; j++) {
            if (i == 1 || i == r) {
                printf("*");
                if (j == d) printf("\n");
                continue;
            }
            if (j == 1) printf("*");
            else if (j == d) printf("*\n");
            else printf(" ");
        }
    }
}

void TamGiacDac(int h) {
    for (int i = 1; i <= h; i++) {
        for (int j = 1; j <= i; j++) {
            printf("*");
        }
        printf("\n");
    }
}

void TamGiacRong(int h) {
    for (int i = 1; i <= h; i++) {
        for (int j = 1; j <= i; j++) {
            if (i == h) {
                printf("*");
                continue;
            }
            if (j == 1 && i != 1) printf("*");
            else if (j == i) printf("*\n");
            else printf(" ");
        }
    }
}

void Bai8(int n) {
    int count = 0;
    int sum = 0;
    printf("Cac uoc so chan cua %d la:\n", n);
    for (int i = 1; i <= n/2; i++) {
        if (n % i == 0) {
            sum += i;
            count++;
            if (i % 2 == 0) printf("%d ", i);
        }
    }
    printf("\nTong tat ca cac uoc cua %d la: %d\n", n, sum);
    printf("So cac uoc so cua %d la: %d", n, count);
}

int Bai9 (int n) {
    //1 * 3 * 5 * ... * (2n+1)
    int result = 1;
    for (int i = 3; i <= 2*n+1; i+=2) result *= i;
    return result;
}

void BangCuuChuong() {
    for (int i = 2; i <= 9; i++) {
        for (int j = 1; j <= 9; j++) {
            printf("%d x %d = %d\n", i, j, i*j);
        }
        printf("------------\n");
    }
}

int main () {
    return 0;
}