Exercise the cyclic statements in C language, and execute the cyclic statements in C Language

Exercise the cyclic statements in C language, and execute the cyclic statements in C Language

Note: All exercise questions are from the introduction to C Language

I. do statements

1. Calculate the sum and average of multiple integers.

# Include <stdio. h> int main (void) {int sum = 0; // and int cnt = 0; // integer number int retry; // judge whether to continue do {int t; printf ("enter an integer:"); scanf ("% d", & t); sum = sum + t; cnt = cnt + 1; printf ("continue? <Yes... 0/No... 9: "); scanf (" % d ", & retry) ;}while (retry = 0); printf (" and % d, average %. 2f. \ N ", sum, (double) sum/cnt); return 0 ;}

 

Ii. whie statements

1. Each integer from 0 to the input positive integer is displayed progressively

# Include <stdio. h> int main (void) {int I, n; printf ("enter a positive integer:"); scanf ("% d", & n); I = 0; while (I <= n) printf ("% d", I ++); // The value of I increases progressively after display printf ("\ n"); return 0 ;}

 

2. Write a program to display all positive and even numbers smaller than the input values in ascending order.

# Include <stdio. h> int main (void) {int I, n; printf ("enter a positive integer:"); scanf ("% d", & n); I = 0; while (I <= n) {I = I + 2; if (I <n) // you must first judge the incremental value, check whether printf ("% d", I) ;}printf ("\ n"); return 0 ;}

 

3. Write a program to show + and-alternately. The total number is equal to the entered integer.

# Include <stdio. h> int main (void) {int num; int I = 0; printf ("positive integer:"); scanf ("% d", & num ); while (I <num) {if (++ I % 2) putchar ('+'); else putchar ('-');} return 0 ;}

 

4. Reverse display of Positive Integers

# Include <stdio. h> int main (void) {int n; do {printf ("enter a positive integer:"); scanf ("% d", & n ); if (n <= 0) puts ("do not enter a non-positive integer. ") ;}While (n <= 0); printf (" the result of reverse display of this integer is "); while (n> 0) {printf (" % d ", n % 10); n/= 10;} puts (". "); Return 0 ;}

 

III. for statements

1. Write a program to display 1234567890 cyclically based on the input integer. The number of digits displayed is the same as the input integer.

# Include <stdio. h> int main (void) {int I, j, n; j = 1; printf ("enter an integer:"); scanf ("% d ", & n); for (I = 0; I <n; I ++) {printf ("% d", j); j ++; if (j> 9) j-= 10;} printf ("\ n"); return 0 ;}

 

2. Compile a program to display the table of high birth and standard weight. Note: The displayed height range and interval are controlled by the entered integer. The standard weight is accurate to the second digit after the decimal point.

# Include <stdio. h> int main () {int beginHigh = 0, endHigh = 0; float weight = 0; int margin = 0; printf ("start value (cm ):"); scanf ("% d", & beginHigh); printf ("end value (cm):"); scanf ("% d", & endHigh ); printf ("interval value (cm):"); scanf ("% d", & margin); for (int I = beginHigh; I <= endHigh; I + = margin) {weight = (I-100) * 0.9; // This is a formula for calculating the standard weight printf ("% d cm \ t %. 2f \ n ", I, weight); // \ t indicates a Tab, equivalent to pressing a Tab key} return 0 ;}

 

3. display all the approximate values of the input integer.

# Include <stdio. h> int main (void) {int I, n; printf ("INTEGER:"); scanf ("% d", & n); for (I = 1; I <= n; I ++) if (n % I = 0) printf ("% d", I); putchar ('\ n'); return 0 ;}

 

4. Write a program and enter an integer to display the integer '*'. Line feed is performed for each display of 5.

# Include <stdio. h> int main () {printf ("enter an integer:"); int a; scanf ("% d", & a); int B = 0; for (int I = 0; I <a; I ++) {if (B = 5) {printf ("\ n"); B = 0 ;} printf ("*"); B = B + 1 ;}}

 

 

Iv. Multiple cycles

1. display the 9-9 multiplication table

#include<stdio.h>int main(void){    int i,j;    for(i = 1;i <= 9;i++){        for(j = 1;j <= 9;j++)            printf("%3d",i * j);        putchar('\n');    }        return 0; } 

 

2. Write a program to add a horizontal and vertical title to the 9-9 multiplication table.

# Include <stdio. h> int main () {int I, j; // print the first line printf ("|"); for (I = 1; I <= 9; I ++) {printf ("% d", I) ;}printf ("\ n"); // print the second line for (I = 1; I <= 32; I ++) printf ("-"); printf ("\ n"); // start printing the 99 multiplication table. Each row must start with a row number for (I = 1; I <= 9; I ++) // row {printf ("% d |", I); for (j = 1; j <= 9; j ++) // column {printf ("% 2d", I * j);} printf ("\ n");} return 0 ;}

 

3. Draw a rectangle

# Include <stdio. h> int main (void) {int I, j; int height, width; puts ("let's draw a rectangle. "); Printf (" high: "); scanf (" % d ", & height); printf (" width: "); scanf (" % d ", & width); for (I = 1; I <= height; I ++) {// The rectangle has a height row for (j = 1; j <= width; j ++) // display width putchar ('*') in each row; putchar ('\ n'); // line feed} return 0 ;}

 

4, (1) display the right angleBottom leftRight triangle of the same waist

# Include <stdio. h> int main (void) {int I, j, len; puts ("right angle at the bottom left of the isosceles right triangle. "); Printf (" side length: "); scanf (" % d ", & len); for (I = 1; I <= len; I ++) {for (j = 1; j <= I; j ++) putchar ('*'); putchar ('\ n');} return 0 ;}

 

 

(2) display the right angleBottom rightRight triangle of the same waist

# Include <stdio. h> int main (void) {int I, j, len; puts ("right angle at the bottom left of the isosceles right triangle. "); Printf (" side length: "); scanf (" % d ", & len); for (I = 1; I <= len; I ++) {for (j = 1; j <= len-I; j ++) putchar (''); for (j = 1; j <= I; j ++) putchar ('*'); putchar ('\ n');} return 0 ;}

 

 

(3) display the right angleUpper leftRight triangle of the same waist

# Include <stdio. h> int main () {int I, j, len; puts ("right angle at the lower left corner of the isosceles right triangle. "); Printf (" side length: "); scanf (" % d ", & len); for (int I = 1; I <= len; I ++) {for (int j = 1; j <= len-I + 1; j ++) {putchar ('*');} putchar ('\ n ');} return 0 ;}

 

 

(4) display the right angleUpper rightRight triangle of the same waist

# Include <stdio. h> int main () {int I, j, len; puts ("right angle at the lower left corner of the isosceles right triangle. "); Printf (" side length: "); scanf (" % d ", & len); for (int I = 1; I <= len; I ++) {for (int j = 1; j <= I; j ++) {putchar ('') ;}for (int j = 1; j <= len-I + 1; j ++) {putchar ('*');} putchar ('\ n');} return 0 ;}

 

 

5. Write a program and enter an integer to display the pyramid shape of the input integer layer.

Tip: line I (I-1) x 2 + 1 '*'

# Include "stdio. h" int main (int argc, char const * argv []) {int n; puts ("Let's plot a pyramid. "); Printf (" the pyramid has several layers: "); scanf (" % d ", & n); for (int I = 1; I <= n; I ++) {for (int j = 1; j <= n-I; j ++) {putchar ('') ;}for (int j = 1; j <= I; j ++) {putchar ('*') ;}for (int j = 1; j <I; j ++) {putchar ('*');} putchar ('\ n');} return 0 ;}

 

Pyramid deformation (1)

# Include <stdio. h> int main () {int I, j, n; puts ("Let's plot a pyramid. "); Printf (" the pyramid has several layers: "); scanf (" % d ", & n); for (I = 1; I <= n; I ++) {for (j = 0; j <n-I; j ++) printf (""); for (j = 1; j <2 * I; j ++) printf ("% d", I); printf ("\ n");} return 0 ;}

 

Pyramid deformation (2)

# Include <stdio. h> int main () {int I, j, n; puts ("Let's plot a pyramid. "); Printf (" the pyramid has several layers: "); scanf (" % d ", & n); for (I = 1; I <= n; I ++) {for (j = 0; j <n-I; j ++) printf (""); for (j = 1; j <= I; j ++) printf ("% d", j); for (j = I-1; j> 0; j --) printf ("% d", j ); printf ("\ n ");}}

 

Summary

Loop is the foundation of C language, so you must practice it well and be skillful. Note:

• Note that the while statement and the do-while statement are differentiated. The former is judged first and then executed, while the latter is executed first and then judged.
• The do statement is executed at least once, while the while statement is not executed once.
• Do not place an empty statement after the for and while statements.
• The loop body of the do statement, even a single statement, can be enclosed by {} to make it a composite Statement (program block), so that the program will be easy to read.