Write a C programm that will calculate the area of triangle, rectangle and circle. Input the choice and values from user.

#include<stdio.h>

void main()
{
    char user;
    float area,l,b,h,w,r,pi=3.1416;

    printf("To calculate the area of\n\nA triangle press 'a'\nA rectangle press 'b'\nA circle press 'c'\n\nInput here:");
    scanf("%c", &user);

    switch(user){

        case 'a':{
            printf("Base: ");
            scanf("%f", &b);
            printf("Height: ");
            scanf("%f", &h);

            area=0.5*b*h;
            printf("Area of the triangle is %.2f square unit", area);
            break;
        }

        case 'b':{
            printf("Length: ");
            scanf("%f", &l);
            printf("Width: ");
            scanf("%f", &w);

            area=l*w;
            printf("Area of the rectangle is %.2f square unit", area);
            break;
        }

        case 'c':{
            printf("Radius: ");
            scanf("%f", &r);

            area=pi*r*r;
            printf("Area of the circle is %.2f square unit", area);
            break;
        }

        default:
            break;

    }
}

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