c - Incorrect variable value incrementing -

i have following code:

#include <stdio.h> #include <ctype.h>  int main(int argc, char **argv) {         int ch, lower, upper = 0;         printf("enter line of text: \n");         while ((ch = getchar()) != eof) {         if (islower(ch)) {                 ch = toupper(ch);                 ++upper;         } else if (isupper(ch)) {                 ch = tolower(ch);                  printf("looking @ lower: %d\n", lower);                 ++lower;                 printf("looking @ lower: %d\n", lower);         }         putchar(ch);         }         printf("hello\n");         printf("\nread %d characters in total. %d converted upper-case, %d lower-case.", upper+lower, upper, lower); } 

for reason upper variable being set correctly, can't work out why lower giving erroneous value. e.g. if type in 'football' says 4195825 converted lower-case, actual output should 1.

i can't see i'm going wrong here.

you haven't initialized lower. it's value indeterminate.

c11: 6.7.9 initialization (p10):

if object has automatic storage duration not initialized explicitly, value indeterminate.

initialize 0.

int ch, lower = 0, upper = 0;