foo.cc: In function 'int main()':
foo.cc:12:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&v[i],&w[i]);
  ~~~~~^~~~~~~~~~~~~~~~~~~~
/tmp/ccHO89Uq.o: In function `main':
foo.cc:(.text.startup+0x7): relocation truncated to fit: R_X86_64_PC32 against symbol `N' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x24): relocation truncated to fit: R_X86_64_PC32 against symbol `M' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x4b): relocation truncated to fit: R_X86_64_PC32 against symbol `M' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x5a): relocation truncated to fit: R_X86_64_PC32 against symbol `v' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x61): relocation truncated to fit: R_X86_64_PC32 against symbol `w' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x8a): relocation truncated to fit: R_X86_64_PC32 against symbol `M' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x9b): relocation truncated to fit: R_X86_64_PC32 against symbol `N' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0xb6): relocation truncated to fit: R_X86_64_PC32 against symbol `w' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0xbd): relocation truncated to fit: R_X86_64_PC32 against symbol `v' defined in .bss section in /tmp/ccHO89Uq.o
foo.cc:(.text.startup+0x19a): relocation truncated to fit: R_X86_64_PC32 against symbol `N' defined in .bss section in /tmp/ccHO89Uq.o
/tmp/ccHO89Uq.o: In function `_GLOBAL__sub_I_N':
foo.cc:(.text.startup+0x1b3): additional relocation overflows omitted from the output
collect2: error: ld returned 1 exit status

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