# 我愛柯世文

cool

#include <stdio.h>
#define SIZE 100

// function to print the dimensional array
void printArray(int a[SIZE][SIZE], int n){
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            printf("%c ", a[i][j]);
        }
        printf("\n");
    }
}

// function to print the menu
void printMenu(){
    printf("Please choose which pattern you want to print: (Enter [1/2/3/4])\n");
    printf("1: Print triangle\n");
    printf("2: Rotate triangle 90 degrees\n");
    printf("3: Rotate specified rotate angle\n");
    printf("4: End program\n");
}

// function to rotate the dimensional array clockwise 90 degree
void rotateArray90Degrees(int begin[SIZE][SIZE], int after[SIZE][SIZE], int n){
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            after[j][i] = begin[(n-1)-i][j];
        }
    }
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            begin[i][j] = after[i][j];
        }
    }
}

// function to rotate the dimensional array clockwise 180 degree
void rotateArray180Degrees(int begin[SIZE][SIZE], int after[SIZE][SIZE], int n){
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            after[(n-1)-i][(n-1)-j] = begin[i][j];
        }
    }
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            begin[i][j] = after[i][j];
        }
    }
}

// function to rotate the dimensional array clockwise 270 degree
void rotateArray270Degrees(int begin[SIZE][SIZE], int after[SIZE][SIZE], int n){
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            after[(n-1)-j][i] = begin[i][j];
        }
    }
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            begin[i][j] = after[i][j];
        }
    }
}

int main(){

    // declare all variables
    int size, mode, angle, tri[SIZE][SIZE] = {0}, tmp[SIZE][SIZE];

    printf("Please enter the size of triangle: ");
    scanf("%d", &size);
    // check whether the input number is within the range
    while(size <= 0){
        printf("The size should be positive. Try again: ");
        scanf("%d", &size);
    }

    // establish the triangle
    for(int i = 0; i < size; i++){
        for(int j = 0; j < size; j++){
            if(i >= j) tri[i][j] = '*';
            else tri[i][j] = '0';
        }
    }

    printMenu();
    scanf("%d", &mode);

    while(mode != 4){

        if(mode == 1){
            // if the input number is 1 will print the triangle
            printArray(tri, size);
            printMenu();
            scanf("%d", &mode);
        }else if(mode == 2){
            // if the input number is 2 will rotate the triangle 90 degree
            rotateArray90Degrees(tri, tmp, size);
            printf("Received. Rotate the triangle 90 degree.\n");
            printMenu();
            scanf("%d", &mode);
        }else if(mode == 3){
            // if the input number is 3 will rotate the triangle in specified angles
            printf("Please enter the specified angle(the angle must be a multiple of 90): ");
            scanf("%d", &angle);
            // check whether the input number is within the range
            while(angle % 90 != 0){
                printf("The input number should be the multiple of 90. Try again: ");
                scanf("%d", &angle);
            }

            printf("Received. Rotate the triangle %d degree.\n", angle);

            // adjust the angle
            while(angle < 0) angle += 360;
            while(angle > 360) angle -= 360;

            if(angle == 0){
                // do nothing
            }else if(angle == 90){
                rotateArray90Degrees(tri, tmp, size);
            }else if(angle == 180){
                rotateArray180Degrees(tri, tmp, size);
            }else if(angle == 270){
                rotateArray270Degrees(tri, tmp, size);
            }

            printMenu();
            scanf("%d", &mode);
        }else{
            // check whether the input number is within the range
            printf("The input number should be 1 to 4. Try again: ");
            scanf("%d", &mode);
        }
    }

    // if the input number is 4 will end the program
    printf("End Program");
}