Understanding C Language Vocabulary Elements

In the world of C programming, mastering its vocabulary elements is fundamental for writing code smoothly.

1. The Six Major Tokens in C Language

There are six key tokens in C language, which are the basic units that make up C code: keywords, punctuation, identifiers, constants, string constants, and operators.

2. Rules for Identifiers

Identifiers are names used to identify variables, functions, etc. The first character must be a letter or an underscore, which is a rule to remember when naming.

3. Postfix Increment and Compound Assignment

Postfix Increment (a++): For example, with a = 5 and b = a++, it will first return the current value of variable a, and then perform the increment operation on a. After execution, b = 5, and a = 6.
Prefix Increment (++a): If a = 5 and b = ++a, it first performs the increment operation on variable a, and then returns the new value. After execution, b = 6, and a = 6.
Compound Assignment: For example, a += 5 is actually equivalent to a = a + 5; looking at j = 2, k = 3, and j *= (k + 3), it is equivalent to j = j * (k + 3), with the calculation being j = 2 * 6 = 12.

Problem 1: Print the ASCII value of a user-input character

Problem 2: Convert days to years, weeks, and days

#include<stdio.h>intmain(){int days, years, weeks, remainingDays;printf("Input days:");scanf("%d",&days); years = days /365; remainingDays = days %365; weeks = remainingDays /7; remainingDays = remainingDays %7;printf("Years: %d\nWeeks: %d\nDays: %d\n", years, weeks, remainingDays);return0;}

Problem 3: Calculate the perimeter and area of a rectangle

#include<stdio.h>intmain(){int length, width, perimeter, area;printf("Input length and width:");scanf("%d %d",&length,&width); perimeter =2*(length + width); area = length * width;printf("Perimeter: %d\nArea: %d\n", perimeter, area);return0;}

Problem 4: Check if a number is divisible by two divisors

#include<stdio.h>intmain(){int dividend, divisor1, divisor2;printf("Input dividend, divisor1, divisor2:");scanf("%d %d %d",&dividend,&divisor1,&divisor2);if(dividend % divisor1 ==0&& dividend % divisor2 ==0){printf("1\n");}else{printf("0\n");}return0;}

Problem 5: Print a power table (powers 1 to 5, integers 1 to 10)

#include<stdio.h>intmain(){int i;printf("Power1\tPower2\tPower3\tPower4\tPower5\n");for(i =1; i <=10; i++){printf("%d\t%d\t%d\t%d\t%d\n", i, i * i, i * i * i, i * i * i * i, i * i * i * i * i);}return0;}

Problem 6: Find and print the size of variables (int, float, double, char)

#include<stdio.h>intmain(){printf("Integer: %lu\n",sizeof(int));printf("Float: %lu\n",sizeof(float));printf("Double: %lu\n",sizeof(double));printf("Character: %lu\n",sizeof(char));return0;}

Understanding C Language Vocabulary Elements

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