Hello Guys
I am new to C programming and as a part of an assignment I have made an ATM algorithm in C. Though the compiler shows no errors, the code goes into an infinite loop after the first input.
Please Help.
Here's the code:

#include<stdio.h>
#include<conio.h>
void main(){
float bal=0,dep=0,withd=0;
int n1,n2;
clrscr();
do{
clrscr();
printf("\n\t\t************************\t\t\n");
printf("\t\tWelcome To ATM Services\n");
printf("\t\tSelect Your Choice:\n");
printf( "\t\t1)Deposit Cash\n\t\t2)Withdraw Cash\n\t\t3)Bank Statement\n\t\t4)Fast Cash\n\t\t5)Exit\n");
printf("\t\t***********************\t\t\n");
scanf("%d",&n1);
switch(n1){
case 1: printf("Enter the amount to be deposited\n");
scanf("%f",&dep);
if(dep>0){
bal+=dep;
printf("You have deposited %f cash. Your current account balance is %f\n",dep,bal); }
else printf("Invalid amount entered\n");
printf("Press any key to continue\n");
break;
case 2: printf("Enter the amount to be withdrawn\n");
scanf("%f",&withd);
if(withd<bal && withd>0){
bal-=withd;
printf("You have withdrawn %f cash. Your current account balance is %f\n",withd,bal);}
else printf("Insufficient funds in your account\n");
printf("Press any key to continue\n");
break;
case 3:  printf("\t\tYour Current Bank Statement Is:\n");
printf("\t\t Your account balance is %f.\n",bal);
printf("Enter any key to continue");
break;
case 4: printf("\t\tWelcome To FastCash\n");
printf("\t\tSelect an alternative:\n");
printf("\t\t1)Rs100\n\t\t2)Rs500\n\t\t3)Rs1000\n");
scanf("%d",&n2);
switch(n2){
case 1: printf("You have chosen to withdraw Rs100\n");
if(bal>=100){
bal-=100;
printf("You have withdrawn Rs100. Your balance is %f\n",bal);
printf("\t\tPlease Collect Your Cash\n");}
else printf("Insufficient Funds in account");
break;
case 2: printf("You have chosen to withdraw Rs500.\n");
if(bal>=500){
bal-=500;
printf("You have withdrawn Rs500. Your account balance is %f\n",bal);
printf("\t\tPlease Collect Your Cash\n"); }
else printf("insufficient Funds");
break;
case 3: printf("You have chosen to withdraw Rs1000\n");
if(bal>=1000){
bal-=1000;
printf("You have withdrawn Rs1000. Your account balance is %f\n",bal);
printf("\t\tPlease Collect Your Cash");}
else printf("Insufficient Funds");
break;
default: printf("\t\tWrong Choice Entered");  } }   }
while(n1!=5) ;
getch();  }

See how your code looks better after I used the astyle beautifier

astyle --style=python --align-pointer=middle --max-code-length=79 atm.c

For human readers, formatting matters in programming

#include<stdio.h>
#include<conio.h>
void main() {
    float bal=0,dep=0,withd=0;
    int n1,n2;
    clrscr();
    do {
        clrscr();
        printf("\n\t\t************************\t\t\n");
        printf("\t\tWelcome To ATM Services\n");
        printf("\t\tSelect Your Choice:\n");
        printf( "\t\t1)Deposit Cash\n\t\t2)Withdraw Cash\n\t\t3)Bank Statement\n\t\t4)Fast Cash\n\t\t5)Exit\n");
        printf("\t\t***********************\t\t\n");
        scanf("%d",&n1);
        switch(n1) {
        case 1: printf("Enter the amount to be deposited\n");
            scanf("%f",&dep);
            if(dep>0) {
                bal+=dep;
                printf("You have deposited %f cash. Your current account balance is %f\n",dep,
                    bal); }
            else printf("Invalid amount entered\n");
            printf("Press any key to continue\n");
            break;
        case 2: printf("Enter the amount to be withdrawn\n");
            scanf("%f",&withd);
            if(withd<bal && withd>0) {
                bal-=withd;
                printf("You have withdrawn %f cash. Your current account balance is %f\n",
                    withd,bal); }
            else printf("Insufficient funds in your account\n");
            printf("Press any key to continue\n");
            break;
        case 3:  printf("\t\tYour Current Bank Statement Is:\n");
            printf("\t\t Your account balance is %f.\n",bal);
            printf("Enter any key to continue");
            break;
        case 4: printf("\t\tWelcome To FastCash\n");
            printf("\t\tSelect an alternative:\n");
            printf("\t\t1)Rs100\n\t\t2)Rs500\n\t\t3)Rs1000\n");
            scanf("%d",&n2);
            switch(n2) {
            case 1: printf("You have chosen to withdraw Rs100\n");
                if(bal>=100) {
                    bal-=100;
                    printf("You have withdrawn Rs100. Your balance is %f\n",bal);
                    printf("\t\tPlease Collect Your Cash\n"); }
                else printf("Insufficient Funds in account");
                break;
            case 2: printf("You have chosen to withdraw Rs500.\n");
                if(bal>=500) {
                    bal-=500;
                    printf("You have withdrawn Rs500. Your account balance is %f\n",bal);
                    printf("\t\tPlease Collect Your Cash\n"); }
                else printf("insufficient Funds");
                break;
            case 3: printf("You have chosen to withdraw Rs1000\n");
                if(bal>=1000) {
                    bal-=1000;
                    printf("You have withdrawn Rs1000. Your account balance is %f\n",bal);
                    printf("\t\tPlease Collect Your Cash"); }
                else printf("Insufficient Funds");
                break;
            default: printf("\t\tWrong Choice Entered");  } }   }
    while(n1!=5) ;
    getch();  }

How do you know that the code goes in an infinite loop ? The only loop here is the do {...} while(n1 != 5);. What happens if you enter 5 for n1 ?

When I run the code, after the first input the output screen goes into an infinite loop.
If I enter 5 for n1, that corresponds to the 5th case of the ATM menu which is for exiting the menu. I employed the do-while loop only if the user wants another go at running the algorithm.
Do tell if there are any logical errors in the code.
Thanks.

I removed the calls clrscr() and getch() because I'm on Linux. When I run the program, it doesn't go into an infinite loop. When I enter 5 in the main menu, it exits the program as expected. I don't think there are logical errors except perhaps some misplaced messages to type any character to continue. What makes you think the program enters an infinite loop?

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