my first basic programs

C program to toggle each character in a string.c

@@ -0,0 +1,18 @@
+#include <stdio.h>
+
+int main()
+{
+    char    str[100];
+    int     counter;
+    printf("Enter a string: ");
+    gets(str);
+    for(counter=0;str[counter]!=NULL;counter++)
+    {
+        if(str[counter]>='A' && str[counter]<='Z')
+            str[counter]=str[counter]+32;   
+        else if(str[counter]>='a' && str[counter]<='z')
+            str[counter]=str[counter]-32;   
+    }
+    printf("String after toggle each characters: %s",str);
+    return 0;
+}

Checking Power of 2 using C program.c

@@ -0,0 +1,27 @@
+#include <stdio.h>
+
+int main()
+{
+    int num;
+    int tempNum,flag;
+    printf("Enter an integer number: ");
+    scanf("%d",&num);
+    tempNum=num;
+    flag=0;
+    while(tempNum!=1)
+    {
+        if(tempNum%2!=0)
+    {
+        flag=1;
+    break;
+    }
+        tempNum=tempNum/2;
+    }
+
+    if(flag==0)
+        printf("%d is power of 2.",num);
+    else
+        printf("%d is not the power of 2.",num);
+
+    return 0;
+}

Convert Feet to Inches.c

@@ -0,0 +1,15 @@
+#include<stdio.h>
+
+int main()
+{
+		int feet,inches;
+
+		printf("Enter the value of feet: ");
+		scanf("%d",&feet);
+
+
+		inches=feet*12;
+
+		printf("Total inches will be: %d\n",inches);
+		return 0;
+}

Count Occurrence of a Digit in a Number using C program.c

@@ -0,0 +1,25 @@
+
+
+#include <stdio.h>
+
+int main()
+{
+    int num,tNum,digit,cnt;
+    int rem;
+    printf("Enter a number: ");
+    scanf("%d",&num);
+    printf("Enter digit to search: ");
+    scanf("%d",&digit);
+    cnt=0;
+    tNum=num;
+    while(tNum>0)
+    {
+        rem=tNum%10;
+        if(rem==digit)
+            cnt++;
+            tNum/=10; 
+}
+     printf("Total occurrence of digit is: %d in number: %d.",cnt,num);
+
+    return 0;
+}

Decimal to Binary Conversion.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+
+int main()
+{
+    int number,cnt,i;
+    int bin[32];
+
+    printf("Enter decimal number: ");
+    scanf("%d",&number);
+    cnt=0;          
+    while(number>0)
+    {
+        bin[cnt]=number%2;
+        number=number/2;
+        cnt++;
+    }
+    printf("Binary value is: ");
+    for(i=(cnt-1); i>=0;i--)
+    printf("%d",bin[i]);
+
+    return 0;
+}

Decimal to Hexadecimal Conversion using C program.c

@@ -0,0 +1,37 @@
+#include <stdio.h>
+
+int main()
+{
+    int number,cnt,i;
+    char    hex[32];    
+    printf("Enter decimal number: ");
+    scanf("%d",&number);
+    cnt=0;             
+    while(number>0)
+    {
+        switch(number%16)
+        {
+            case 10:
+                hex[cnt]='A'; break;
+            case 11:
+                hex[cnt]='B'; break;
+            case 12:
+                hex[cnt]='C'; break;
+            case 13:
+                hex[cnt]='D'; break;
+            case 14:
+                hex[cnt]='E'; break;
+            case 15:
+                hex[cnt]='F'; break;
+            default:
+                hex[cnt]=(number%16)+0x30;  
+        }
+        number=number/16;
+        cnt++;
+    }
+     printf("Hexadecimal value is: ");
+     for(i=(cnt-1); i>=0;i--)
+     printf("%c",hex[i]);
+
+    return 0;
+}

Decimal to Octal Conversion using C program.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+
+int main()
+{
+    int number,cnt,i;
+    int oct[32];
+
+    printf("Enter decimal number: ");
+    scanf("%d",&number);
+    cnt=0;              
+    while(number>0)
+    {
+        oct[cnt]=number%8;
+        number=number/8;
+        cnt++;
+    }
+    printf("Octal value is: ");
+    for(i=(cnt-1); i>=0;i--)
+    printf("%d",oct[i]);
+
+    return 0;
+}

Octal to Decimal Conversion using C program.c

@@ -0,0 +1,25 @@
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
+int main()
+{
+    char oct[32]={0};
+    int  dec,i;
+    int  cnt;   
+
+    printf("Enter octal value: ");
+    gets(oct);
+
+    cnt=0;
+    dec=0;
+    for(i=(strlen(oct)-1);i>=0;i--)
+    {
+        dec= dec+ (oct[i]-0x30)*pow((double)8,(double)cnt);
+        cnt++;
+    }
+
+    printf("DECIMAL value is: %d",dec);
+
+    return 0;
+}

Print Alphabets in Upper and Lower case using C program.c

@@ -0,0 +1,16 @@
+
+
+#include <stdio.h>
+
+int main()
+{
+    char i;
+     printf("Capital (upper) case characters:\n");
+    for(i='A'; i<='Z'; i++)
+        printf("%c ",i);
+    printf("\n\nLower case characters:\n");
+    for(i='a'; i<='z'; i++)
+        printf("%c ",i);
+
+    return 0;
+}

Print all PRIME numbers from 1 to N using C program.c

@@ -0,0 +1,34 @@
+#include <stdio.h>
+
+int checkPrime(int num)
+{
+    int i;
+    int flg=0;
+    for(i=2;i<(num-1);i++)
+    {
+        if(num%i==0) 
+       {
+            flg=1;
+            break;
+        }
+    }
+    if(flg) return 0;
+    else return 1;
+}
+
+int main()
+{
+    int i,n;
+
+    printf("Enter the value of N: ");
+    scanf("%d",&n);
+
+    printf("All prime numbers are from 1 to %d:\n",n);
+    for(i=1;i<=n;i++)
+    {
+        if(checkPrime(i))
+            printf("%d,",i);
+    }
+
+    return 0;
+}

checking wheather the number is perfect or not.c

@@ -0,0 +1,21 @@
+#include <stdio.h>
+
+ int main()
+{
+    int num,loop;
+    int sum;
+    printf("Enter an integer number: ");
+    scanf("%d",&num);
+    sum=0;
+    for(loop=1; loop<num;loop++)
+    {
+        if(num%loop==0)
+        sum=sum+loop;
+    }
+     if(sum==num)
+    printf("%d is a perfect number.",num);
+    else
+    printf("%d is not a perfect number.",num);
+
+    return 0;
+}